Develop Bugs

[Q] Lost LTE after switching to KitKat

I decided to give Kit Kat another try a few days ago, but since then I have not been able to connect to LTE.
Prior to flashing I was running CM10.2 and my LTE was working fine. I initially lost LTE when I flashed PACMAN. I have also tried AOSB/ProBAM and Beanstalk. None of the Kit Kat roms gave me LTE so I gave up and restored CM10.2, but afterward I was still not getting any LTE connection.
I tried flashing the MD4 modem, but that didn't seem to fix anything. I've also heard that going back to stock could help, but I'd rather not have Knox if I don't have to use it. Which stock ROM here on XDA would be the best (Not planning on using the ROM. I just want LTE and then will flash back to Kit Kat)? Would a different modem fix my LTE issues? Is MK3 better than MD4, or are there any newer modems I should try?
Thanks for the help!

snak1e said:
I decided to give Kit Kat another try a few days ago, but since then I have not been able to connect to LTE.
Prior to flashing I was running CM10.2 and my LTE was working fine. I initially lost LTE when I flashed PACMAN. I have also tried AOSB/ProBAM and Beanstalk. None of the Kit Kat roms gave me LTE so I gave up and restored CM10.2, but afterward I was still not getting any LTE connection.
I tried flashing the MD4 modem, but that didn't seem to fix anything. I've also heard that going back to stock could help, but I'd rather not have Knox if I don't have to use it. Which stock ROM here on XDA would be the best (Not planning on using the ROM. I just want LTE and then will flash back to Kit Kat)? Would a different modem fix my LTE issues? Is MK3 better than MD4, or are there any newer modems I should try?
Thanks for the help!
Click to expand...
Click to collapse
Any of the ROMS that have [TW] in the title should work. Full Knox only comes with flashing a tar file in ODIN, because your flashing every partition of the phone. Modified stock ROM zips do not have knox, unless otherwise noted. Make sure to do a prl and profile update when you flash to stock.
sent from my Gs3

joeyhdownsouth said:
Any of the ROMS that have [TW] in the title should work. Full Knox only comes with flashing a tar file in ODIN, because your flashing every partition of the phone. Modified stock ROM zips do not have knox, unless otherwise noted. Make sure to do a prl and profile update when you flash to stock.
sent from my Gs3
Click to expand...
Click to collapse
Flashed Wicked Sensations last night with the MK3 modem and I seemed to be getting LTE as soon as that booted. Updated my PRL and Profile, and then wiped. Installed AOSB again, and I seemed to be getting LTE until I rebooted. After the first reboot I seem to be stuck in 3G again.

Im currently running AOSB on 2 devices. When I first flashed them, I had the same issue until I rebooted the phone. After that I never had this issue again.
sent from my Gs3

joeyhdownsouth said:
Im currently running AOSB on 2 devices. When I first flashed them, I had the same issue until I rebooted the phone. After that I never had this issue again.
sent from my Gs3
Click to expand...
Click to collapse
I think that's the opposite of what happened to me. My status bar said I had LTE when I first booted AOSB (this was after flashing/wiping TW). After the first reboot it connected to 3G and I haven't seen the LTE signal since.
I have updated the APNs, but I was using the same APNs for a while and had LTE on CM10.2 with them.

snak1e said:
I think that's the opposite of what happened to me. My status bar said I had LTE when I first booted AOSB (this was after flashing/wiping TW). After the first reboot it connected to 3G and I haven't seen the LTE signal since.
I have updated the APNs, but I was using the same APNs for a while and had LTE on CM10.2 with them.
Click to expand...
Click to collapse
This is something wierd with Kitkat. I do not believe a fix has been found just yet. but if you dial *#*#info#*#* on most phones you can get into the phone systems and turn LTE back on.

ShrekOpher said:
This is something wierd with Kitkat. I do not believe a fix has been found just yet. but if you dial *#*#info#*#* on most phones you can get into the phone systems and turn LTE back on.
Click to expand...
Click to collapse
I didn't know about this menu. Thanks for that. I went into Phone Info and tried selecting LTE only but it didn't connect to anything. Not sure what that means. There are other
There are some other options in there for networks (e.g. TD-SCDMA, CDMA auto). Would any of them help picking up Sprint LTE?
Other options include:
Turn off radio, CellInfoListRate
Turn on IMS registration required
Turn on SMS over IMS
Turn on lte ram dump
SMSC:_____________ Update Refresh

snak1e said:
I didn't know about this menu. Thanks for that. I went into Phone Info and tried selecting LTE only but it didn't connect to anything. Not sure what that means. There are other
There are some other options in there for networks (e.g. TD-SCDMA, CDMA auto). Would any of them help picking up Sprint LTE?
Other options include:
Turn off radio, CellInfoListRate
Turn on IMS registration required
Turn on SMS over IMS
Turn on lte ram dump
SMSC:_____________ Update Refresh
Click to expand...
Click to collapse
KitKat roms are currently having data issues. You could try backing up your current KK rom and go back to Stock, update prl and backup your DNS settings then go back to your backed up KK rom and restore from the dns settings you backed up.

How does one downgrade from kitkat to jellybean? I tried to just flash a jellybean ROM with a clean install and got an error?
Sent from my SPH-L710 using Tapatalk

TheManiac said:
How does one downgrade from kitkat to jellybean? I tried to just flash a jellybean ROM with a clean install and got an error?
Sent from my SPH-L710 using Tapatalk
Click to expand...
Click to collapse
What error ad you getting exactly?
Sent from my SPH-L710 using Tapatalk

djpabz23 said:
What error ad you getting exactly?
Sent from my SPH-L710 using Tapatalk
Click to expand...
Click to collapse
It says something to do with missing a partition?
Sent from my SPH-L710 using Tapatalk

snak1e said:
I decided to give Kit Kat another try a few days ago, but since then I have not been able to connect to LTE.
Prior to flashing I was running CM10.2 and my LTE was working fine. I initially lost LTE when I flashed PACMAN. I have also tried AOSB/ProBAM and Beanstalk. None of the Kit Kat roms gave me LTE so I gave up and restored CM10.2, but afterward I was still not getting any LTE connection.
I tried flashing the MD4 modem, but that didn't seem to fix anything. I've also heard that going back to stock could help, but I'd rather not have Knox if I don't have to use it. Which stock ROM here on XDA would be the best (Not planning on using the ROM. I just want LTE and then will flash back to Kit Kat)? Would a different modem fix my LTE issues? Is MK3 better than MD4, or are there any newer modems I should try?
Thanks for the help!
Click to expand...
Click to collapse
ohhh i had this issue but i figured it out for pacman and most roms just download nova launcher and when you do create a shortcut on nova ad click on setting an it should say apn once there u open it and youll see where it says ehprd something like that click on it and go all the way to the bottom and change where it says bearer to ehrpd and lte should work ^_^

Ok so I finally got it working, although I'm not sure what was wrong with everything in the first place. My buddy said Cyanogenmod screwed up a recent ROM, so maybe that code was in one of the ROMs I was using.
Each time I flashed back to TouchWiz (I ended up using Wicked Sensations) I could get 4G/LTE. I ran a **72786*, did a PRL & profile update. Prior to finding a working ROM, when I went back to BeanStalk/PACMAN I would lose LTE. After I found the updated BeanStalk ROM I flashed and it still had LTE! Happy days!
At this point I was able to send MMS somehow, but phone was having problems being recognized by the network. I could connect to LTE but couldn't use the data. After I updated the APNs everything started working again.

snak1e said:
Ok so I finally got it working, although I'm not sure what was wrong with everything in the first place. My buddy said Cyanogenmod screwed up a recent ROM, so maybe that code was in one of the ROMs I was using.
Each time I flashed back to TouchWiz (I ended up using Wicked Sensations) I could get 4G/LTE. I ran a **72786*, did a PRL & profile update. Prior to finding a working ROM, when I went back to BeanStalk/PACMAN I would lose LTE. After I found the updated BeanStalk ROM I flashed and it still had LTE! Happy days!
At this point I was able to send MMS somehow, but phone was having problems being recognized by the network. I could connect to LTE but couldn't use the data. After I updated the APNs everything started working again.
Click to expand...
Click to collapse
How did you update your APN's?

try switching to philz touch recovery where it will give you 2 options....do clean to install a new rom.....if works....thks appreciated...safe flashing and live prosperous

djpabz23 said:
How did you update your APN's?
Click to expand...
Click to collapse
This should work http://forum.xda-developers.com/showthread.php?t=1794956

[Q] CM11.0, 20140608, M7 Snapshot - Unable to get signal from radio

I started to experiment with different custom ROMs available for the d2att (now, apparently called the d2lte). My phone is using TeamWin 2.6.3.1 for recovery, I have been using it for everything. So far I have only been familiar with two certain ROMs: Cyanogenmod and CarbonROM. I have not flashed anything except for the recovery.
I complete the installation of my new ROM by first wiping cache, dalvik, data and system. My ROMs are stored on an external SD.
CarbonROM was the first one to be installed, but I found it quite buggy and unstable. I have since been using different snapshots of CM to test functionality and stability...since I plan to hang up my LG G2 and start using my SGS3 w/7200mAh battery as my daily phone. So it needs to be very reliable. I also enjoy picking with settings so the more settings the better.
So, question number #1:
When I install CM the normal way, add my APN, and select the proper mobile network mode, how come I cannot get a signal, no matter what I try? I have searched around many forums for the answer to this...many have nothing to do with my problem or are using different phones. I can confirm my SIM card works, as it was used in my LG G2. Carrier is Virgin Mobile Canada. Network mode is GSM/WCDMA Auto. It does not work with any other modes including Global.
Q #2:
If I plan on using custom KK (4.4.2) ROMs, is there anything extra I need to flash to the phone in order for the cell radio to work successfully? When I researched this, I found lots of people talking about flashing a custom bootloader, but I could not find an exact answer to my question. I would rather not brick my phone by attempting this blindly.
Q #3:
Since I am looking for a reliable custom ROM, is CM the best developer to choose? Is there a more reliable ROM out there?
Mike
EDIT: I did more reaseach on bootloaders and modem firmware and found that my bootloader is already at the most recent version. I did find however that my modem firmware was out of date, so I updated from UEMK5 to UEND3. This however did not solve my problem as I still have no service...
I am contemplating now about starting from scratch and wiping my internal storage... will this help or is it unnecessary?

For question # 1, do you have a proper imei after installing CM11? You can check it in the dialer by typing in *#06#.
For question #2, the modem must be compatible with the bootloader. Custom ROMs will only install if the phone has a compatible bootloader.
For question #2, I prefer Validus which is an AOSP-based ROM.

audit13 said:
For question # 1, do you have a proper imei after installing CM11? You can check it in the dialer by typing in *#06#.
For question #2, the modem must be compatible with the bootloader. Custom ROMs will only install if the phone has a compatible bootloader.
For question #2, I prefer Validus which is an AOSP-based ROM.
Click to expand...
Click to collapse
I have an IMEI number. That is what has me kind of confused...everything is there to show signal, it's just that it will not pick up a tower. When I throw a SIM card in it recognizes it. One thing to also mention is it pins the signal at 0, -1, or 258692378... or another outrageous number.

First things first have you followed the method of going back to a stock TW ROM, obtaining a GPS lock, and then flashed your Custom KitKat rom?
Sent from Mission Control

UnknownTroll1 said:
First things first have you followed the method of going back to a stock TW ROM, obtaining a GPS lock, and then flashed your Custom KitKat rom?
Sent from Mission Control
Click to expand...
Click to collapse
I am now on stock 4.3 firmware. I have obtained a GPS lock.
No service at all.
But... I had a funny feeling, so I went into stock android recovery and wiped cache...and voila, service!
Only problem is, I'm losing it almost constantly. The only way to fix it is by wiping the cache, but I can't keep doing that whenever I lose service.
Will I be okay to flash the custom recovery and custom ROM at this point?

Do you have the latest modem installed?

mpelley92 said:
I am now on stock 4.3 firmware. I have obtained a GPS lock.
No service at all.
But... I had a funny feeling, so I went into stock android recovery and wiped cache...and voila, service!
Only problem is, I'm losing it almost constantly. The only way to fix it is by wiping the cache, but I can't keep doing that whenever I lose service.
Will I be okay to flash the custom recovery and custom ROM at this point?
Click to expand...
Click to collapse
If you are still on the Stock TW ROM here is a method to try. It will clear most of your mobile data problems.
1. Enter the Samsung service mode by typing this code into the dial pad *#197328640#
2. Then go to Mainmenu>UMTS>Common>NV REBUILD>NV REBUILD> (Important: don't exit the menu yet!)
3. Wait 30+ sec
4. Long press power button and select "Restart / Reboot"
5. Now check your GPS from any software that may use GPS like "Maps" or "GPS Status"
Credit: S3Rx ROM Development Thread.
EDIT: Afterwards you should be good to go on your custom ROM. This issue seems to have arisen when a d2lte build broke most people's LTE/Mobile data.
Sent from Mission Control

UnknownTroll1 said:
If you are still on the Stock TW ROM here is a method to try. It will clear most of your mobile data problems.
1. Enter the Samsung service mode by typing this code into the dial pad *#197328640#
2. Then go to Mainmenu>UMTS>Common>NV REBUILD>NV REBUILD> (Important: don't exit the menu yet!)
3. Wait 30+ sec
4. Long press power button and select "Restart / Reboot"
5. Now check your GPS from any software that may use GPS like "Maps" or "GPS Status"
Credit: S3Rx ROM Development Thread.
EDIT: Afterwards you should be good to go on your custom ROM. This issue seems to have arisen when a d2lte build broke most people's LTE/Mobile data.
Sent from Mission Control
Click to expand...
Click to collapse
I am still unable to get service. This time it is pinned at -113. I am although, registered on a network. Not able to make calls or text.

mpelley92 said:
I am still unable to get service. This time it is pinned at -113. I am although, registered on a network. Not able to make calls or text.
Click to expand...
Click to collapse
Yea at this point I am stumped. I guess its a hardware issue. But before calling quits what is your baseband and boot loader?
Sent from Mission Control

UnknownTroll1 said:
Yea at this point I am stumped. I guess its a hardware issue. But before calling quits what is your baseband and boot loader?
Sent from Mission Control
Click to expand...
Click to collapse
Bootloader and baseband: I747MVLUEMK5

mpelley92 said:
Bootloader and baseband: I747MVLUEMK5
Click to expand...
Click to collapse
You're running the most recent release so I'm not sure what's causing the issue.

audit13 said:
You're running the most recent release so I'm not sure what's causing the issue.
Click to expand...
Click to collapse
I have found the problem with the service. I live in an area where signal is not too great. My LG G2 has a tendency to pick up the correct tower for my area, but my Galaxy S3 does not choose the same tower... It looks for one in a completely different direction.
Forgive me, this thread is going to take a bit of a turn.
Is there any way to choose which cell tower the phone connects to? In my area there is one directly east and the other is directly west. I need the western tower in order to make/receive calls/text and in order to get any data reception. Right now where my phone sits, it does not connect to the western tower so I cannot use it. I used OpenSignal to observe which tower both phones connect to.
The other issue I found is my extended battery (Anker 7200) also interferes with reception quite a bit. In town, it's not noticeable. But out on my acreage it stops my phone from getting any signal. I compared it to my LG G2 and my Galaxy S3 with the old 2100mAh battery. The G2 hovers around -95, S3 w/OEM battery at -101 and the S3 w/Anker battery at -113 (no service).
Mike

mpelley92 said:
Is there any way to choose which cell tower the phone connects to? In my area there is one directly east and the other is directly west. I need the western tower in order to make/receive calls/text and in order to get any data reception. Right now where my phone sits, it does not connect to the western tower so I cannot use it. I used OpenSignal to observe which tower both phones connect to.
Mike
Click to expand...
Click to collapse
Try changing the mode to LTE only under your settings. This may force the stronger connection.

x0ne215 said:
Try changing the mode to LTE only under your settings. This may force the stronger connection.
Click to expand...
Click to collapse
Unfortunately that won't work either. In my area I can only pick up HSPA....

mpelley92 said:
Unfortunately that won't work either. In my area I can only pick up HSPA....
Click to expand...
Click to collapse
Hmm. Out of curiosity, have you tried a different ROM on 4.4.2? I've had weird issues with ROMs and signal, ie MIUI caused me to have my signal cut in and out at random intervals. Worth a shot at least. I've been using SlimKat if you want one for reference (probably the quickest download due to size).
Unfortunately all I can suggest is trying to play with tasker and seeing if you can get it to skip over the crap tower, but to my knowledge there's no way to prevent connection to said tower.
I guess if you wanna get into a gray area you could modify said tower....but I claim no responsibility for your actions with that

x0ne215 said:
Hmm. Out of curiosity, have you tried a different ROM on 4.4.2? I've had weird issues with ROMs and signal, ie MIUI caused me to have my signal cut in and out at random intervals. Worth a shot at least. I've been using SlimKat if you want one for reference (probably the quickest download due to size).
Unfortunately all I can suggest is trying to play with tasker and seeing if you can get it to skip over the crap tower, but to my knowledge there's no way to prevent connection to said tower.
I guess if you wanna get into a gray area you could modify said tower....but I claim no responsibility for your actions with that
Click to expand...
Click to collapse
I've been using Liquidsmooth the past few nights and am losing signal more than ever.
Would the OS control how the modem is used? I would think that it's hardware only that changes how and when you get service.
I'm going to try the UEND3 modem firmware and see if that makes a difference. Also going to try SlimKat like you suggested.

Can't make calls out (Random only on network mode WCDMA/GSM (Auto Connect)

Hi.
I have a Samsung Galaxy S3 T999 model on carrier T-mobile. Lately the phone has gone nuts and will get stuck on dialing out and will never make the call. Everything else works fine. Sometimes I have to soft reset, pull the battery and that will fix it for a call or two, then it will get stuck again. I have contacted T-mobile about this over 5 times and none of them can help. We tried to change the sim, reset the account. Etc and nothing. I have reset the cache, factory reset and even put in a good working sim card from another phone and the same problem comes up. During my latest troubleshooting I have narrowed it down to where I switch "network mode" to GSM only and that can make calls out all the time, but the data stays on E (which then I can't use the internet because it's so slow) When I switch back to auto I am sometimes able to place calls again, but only a few. After I test a few calls and leave the phone for a few minutes the phone will get stuck back on not making calls out and just saying "dialing".
Has anyone had the same problems or know of a fix? Currently I have been trying to flash the modem to different versions to see if that fixes the problem. The first two modems I have flashed did not work and came up with "unknown baseband".
If anyone can help I greatly appreciate it.

This is a known issue with 4.3.. What firmware are you on? Assuming you flashed the correct baseband for your device, the 'unknown baseband' message sounds like you are in 4.3 but what build? You can't flash any modems successfully less than 4.3
Sent from my SGH-M919 using Tapatalk

serio22 said:
This is a known issue with 4.3.. What firmware are you on? Assuming you flashed the correct baseband for your device, the 'unknown baseband' message sounds like you are in 4.3 but what build? You can't flash any modems successfully less than 4.3
Sent from my SGH-M919 using Tapatalk
Click to expand...
Click to collapse
I was previously on 4.1.2 when the problem first started. I updated it to 4.3 and still the same problem.
jss15j.t999uvuenc2 build. (I put this one back on last night so at least I can use the phone today when I am at work)
I was just hoping that the device didn't go bad when it was on 4.1.2 because it was working just fine before the problem started.

Was it official update to NC2 by OTA/Odin or you just flashed a ROM?
Sent from my SGH-M919 using Tapatalk

serio22 said:
Was it official update to NC2 by OTA/Odin or you just flashed a ROM?
Sent from my SGH-M919 using Tapatalk
Click to expand...
Click to collapse
NC2 was OTA. After doing some searches it said that OTA could of been corrupt, so I went and downloaded KIES and did a reinstall that way.
When I upgraded to 4.3 I tried that default baseband out and had the same problems. That is when I was searching on google and came across this forum and also the thread about flashing modems.

What APN (Access Point Name) are you on ? Also what is your Preferred Network Type set to ? Its located in Settings > More I think.(I don't use Stock Firmware)

Perseus71 said:
What APN (Access Point Name) are you on ? Also what is your Preferred Network Type set to ? Its located in Settings > More I think.(I don't use Stock Firmware)
Click to expand...
Click to collapse
APN is epc.tmobile.com
Network Mode current set to GSM (the only way I can make calls out without the problem occuring)
WCDMA/GSM (Auto Connect) is what it should be on so my data is at 4G, but the calls is the problem here

I am not sure but can you check the settings of the Dialer to see if there is ways to choose Lookup providers ?

Perseus71 said:
I am not sure but can you check the settings of the Dialer to see if there is ways to choose Lookup providers ?
Click to expand...
Click to collapse
Nope don't see anything in the dialer about selecting a provider..

Its supposed to be something about Choose Lookup Providers. At least that's the way it is on AOSP.

I suggest Odin flashing the stock NC2 firmware and then factory resetting from stock recovery. (Backup first of course!) If it is still an issue, it will most likely be a hardware problem. From what you have said so far, I believe that you will find this to be the case. Could've been due to damage from a drop, or even overheating at some point. Or it could just be that its simply due to hardware degradation over time.

[Q] Att GS3 No calls over LTE

Hello all,
I have a GS3 with the following info:
ROM: SlimKat -4.4.4.build.7.0-OFFICIAL-5979
Baseband: I747UCUFNE4 (just flashed and cleard cache after)
Kernel: 3.4.101-cyanogenmod-g411b453
I just flashed this rom (after rooting the stock 4.4.2 via towelroot) and am unable to make calls over LTE. Here is what happens:
1. I have full LTE reception (yes it is actually LTE because I am on a cyanogenmod rom and it displays LTE in the top)
2. I make the call
3. I watch the signal change from LTE to 3g to H+, then disconnect.
4. For some towers, the call will go through, provided I am connecting via H+
5. If I go to *#*#INFO#*#* and make the phone settings "LTE ONLY", I am unable to call even when I have good LTE signal.
Whats strange is that Data, seems UNAFFECTED, I can keep in in LTE mode and browse the web as well as send text messages.
Any thoughts?

UPDATE:
I just flashed a new rom (dirty unicorn) and completely wiped the built in memory. I did not install any apps or even sign into my google account.
The problem is still there...
I called AT&T and they didn't seem to see anything wrong, though the tech I got did not sound like she knew what the issue could be...

That's normal. I don't know of any network/phone that has implemented VoLTE yet. (Though I haven't done any research on it either so there might me some that do.) Currently LTE is a data only connection; it doesn't handle calls. So it's supposed to fall back to H+ when you make a call.
[Edit]: I did some "Research" (a.k.a. used the search bar *hint hint*) and what I said above isn't entirely true. I think the I747 is capable of VoLTE but AT&T, being the stickler that they are, doesn't allow it. Here's an old thread that most likely still applies: http://forum.xda-developers.com/showthread.php?t=1791955
Also, this should've been posted in Q&A. If there's any mods here, could ya do us all a favor and move this thread?

Omega Hunter said:
That's normal. I don't know of any network/phone that has implemented VoLTE yet. (Though I haven't done any research on it either so there might me some that do.) Currently LTE is a data only connection; it doesn't handle calls. So it's supposed to fall back to H+ when you make a call.
[Edit]: I did some "Research" (a.k.a. used the search bar *hint hint*) and what I said above isn't entirely true. I think the I747 is capable of VoLTE but AT&T, being the stickler that they are, doesn't allow it. Here's an old thread that most likely still applies: http://forum.xda-developers.com/showthread.php?t=1791955
Click to expand...
Click to collapse
Thanks for the reply. I have also noticed that I am flat out unable to make calls at my home (different tower?) when I have LTE enabled. If I switch to 3G only, then everything works fine...cept I only get 3G speeds. I definitely did not have this problem when I was previously running the same version of SlimKat (I reverted back to stock for a bit) but I also don't know whether AT&T changed something. I am looking to try a rooted version of of the latest stock rom next.
Omega Hunter said:
Also, this should've been posted in Q&A. If there's any mods here, could ya do us all a favor and move this thread?
Click to expand...
Click to collapse
Absolutely. I realized that mistake right after I clicked post I wish the OP could move the thread after it was posted.

scales11 said:
Thanks for the reply. I have also noticed that I am flat out unable to make calls at my home (different tower?) when I have LTE enabled. If I switch to 3G only, then everything works fine...cept I only get 3G speeds. I definitely did not have this problem when I was previously running the same version of SlimKat (I reverted back to stock for a bit) but I also don't know whether AT&T changed something. I am looking to try a rooted version of of the latest stock rom next.
Absolutely. I realized that mistake right after I clicked post I wish the OP could move the thread after it was posted.
Click to expand...
Click to collapse
I just reported it to the mods to have it moved to Q&A. No big deal. We all make mistakes. That's what the mods are here for.

You'll always be on 3G/H+ when using voice. If it's dropping calls, flash a different modem to see if that works.
Sent from my SAMSUNG-SGH-I747 using XDA Free mobile app

AT&T voice calls cannot be done via LTE regardless of the ROM. LTE is currently data only. When on LTE, the phone should switch to 3G/H+ when on voice calls. If you select LTE ONLY, you will not be able to make voice calls since the phone is locked in to the LTE bandwidths only.
Sent from my SAMSUNG-SGH-I747

Well I talked to AT&T and they said that things should be OK on their end (I am on the east coast).
Here is a video of exactly what happens:
http://youtu.be/zHcJ7q0NwRs
NOTE: I do not have any problems with the 3g, yet the LTE just hangs up on its own. In the video, I manually hung up the 3g call.
I don't think I can use a different modem for AT&T with a 4.4 rom....can I?

pretty sure your modem and bootloader have to match.
err on the side of kindness

mrrocketdog said:
pretty sure your modem and bootloader have to match.
err on the side of kindness
Click to expand...
Click to collapse
You may be correct...how do I check which boot loader I have?
Baseband: I747UCUFNE4
Build Number: slim_d2lteuserdebug 4.4.4 KTU84Q 5979 test-keys
ROM: SlimKat -4.4.4.build.7.0-OFFICIAL-5979
Kernel: 3.4.101-cyanogenmod-g411b453

install, if dont have ," terminal emulator" from playstore and type in...
su (enter)(this gives SU permission)...then type....
"getprop ro.bootloader" (enter)(& with the space-without exclamation marks).
sorry if that is confusing.....
SU
getprop ro.bootloader
there, maybe better. lol
err on the side of kindness

Not confusing at all. I know a little linux.
Seems like my bootloader matches:
Bootloader = I747UCUFNE4

Ok??? Does making a phone call on the stock ROM do the same thing? Sounds like you were on official stock when you rooted. If you made a nandroid of the stock, I would go back and check if you have not already.
Sent from my SAMSUNG-SGH-I747
---------- Post added at 01:12 AM ---------- Previous post was at 01:11 AM ----------
Or try a modified stock ROM.
Sent from my SAMSUNG-SGH-I747

Well here is the overall path:
1. Had stock-->everything worked
2. Rooted and moved to SlimKat-->everything worked
3. Went back to stock-->used Odin and flashed a 4.1.1, then upgraded to 4.1.2, then upgraded to 4.3, then 4.4.x (all stock), everything worked
4. I remembered why I hated touchwiz so much so I rooted using towelroot, installed clockworkmod
5. Installed SlimKat --> Did not notice problem for a few days. Then problem began.

Poor Cellular Reception After COI5 Firmware Update

I flashed the firmware for COI5 manually via odin and ever since then I cannot connect to LTE. Furthermore, I can barely connect to any signal. The bars show up, but it often takes a while for the 4G icon to show up. When it does, I am still not able to place a call, with Wi-Fi calling being the only hope I have to do so, but calls placed to me that way go straight to voicemail, so I have to call out from my phone.
Note: Knox is tripped, as I was rooted. I am also in an area where I alway get full bars of LTE, so location is not the issue.
Troubleshooting steps I have tried:
Reflashing COI5 firmware via odin.
Adding the LTE APN for T-Mobile.
Using Smart Switch to do emergency recovery.
Flashing BOH6 firmware (did not work as I don't believe you can downgrade firmware, was worth a shot anyways).
Flashing different custom ROMs (all repeated the same problem, which is how I narrowed it down to having to do with the firmware).
I am currently running completely stock at the moment. If anybody has any suggestions on what I should try next or how I can fix this, I would greatly appreciate it.