Develop Bugs

[Q] Enable USB audio out in kernel

I want to use a tablet as my car head unit, iPads are able to use usb for a digital audio output, I can't post the video yet but there is one on youtube detailing what they use in a iPad car install
Could someone add the functionality to a GNexus CDMA kernel for me to try out in wiring up my stereo? Here is an ongoing discussion to get it enabled on all 4.0.X devices by google but again I can't post the link for the discussion or to vote on the google page.

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USB audio works on my Allwinner A10 tablet witn "Unofficial CyanogenMod 9 for many AllWinner A10 tablets" firmware from Christian Troy

USB DAC support

Hi all,
This is my first post / thread, let me start by saying thanks to all of you !
I am another happy owner of a nexus phone
Our official android 4.1 version does not support USB DACs, and perhaps we can all ask for support at code dot google
Many audiophiles and headfiers already own USB DACs. Think of them as ‘sound cards’ or ‘USB audio devices’ . DAC is actually an acronym for Digital to Analog Converter. And ‘usb audio’ is a standard as you can see in usb dot org
I can do some alpha / beta testing if any new image with usb audio support enabled comes up, just let me know. Or feel free to suggest any other way of enabling usb audio.
I am not talking about android-only docking stations but regular hifi DACs. There are even portable DACs to take with you on road !
™

+1
Also to have this link to keep track of the issue: http://code.google.com/p/android/issues/detail?id=24614

mengsuan , Thank you for providing a link to code dot google, I am a newbiew so I can’t post links yet.
S III seems to be the best choice right now for audiophiles on the road
To tell you the truth I expected all 4.1 phones to support usb audio out of the box. It was my fault, I should have read the articles referring to usb audio support better.
Hopefully the community will help and provide some custom image for Galaxy Nexus even before google does.

[Q] USB Audio Support for CM10/d2att ROM

Is there any way to get USB audio working for the Samsung Galaxy Dock? I've tried using the "Galaxy Dock Sound Redirector" application with no luck. The dev of the application notes:
Please have the CM dev supporting your model verify the correct mapping exists between the ROM audio device and the kernel audio path (commonly set in libaudio).
Example: DEVICE_OUT_ANLG_DOCK_HEADSET in ROM should map to the path PLAYBACK_EXTRA_DOCK in the kernel.
Perhaps there is a custom kernel that fixes this?

I'd also like to chime in on this with the Verizon S3 (d2vzw). No dock/USB audio, and the sound redirector doesn't work. App creator gave me the same suggestion.

TCL 50EP680 5.1 sound problems on Home Theater receiver

Hello everybody,
I'm new on XDA forum, I explain you my problem.
My home theater receiver works fine (5.1 sounds) when :
- I look TV channels
- I use the TCL multimedia centrer (dlna), but this player crashes frequently it's unusefull
But when using android apps, I get a 2.0 sound on my receiver.
Has somebody tried Android apps like Plex, Kodi, Youtube, DS Station, .... and could hear 5.1 sounds on a his home theater receiver ?
Different ROM versions tested :
- RT51_Android P_V252 Software => NOT OK
- RT51_Android P_V270 Software => ?
- RT51_Android P_V288 Software => NOT OK
Thanks,

I have got an 65ep660 , and exactly the same problem,
Only the tcl mediacenter app and netflix are ok about 5.1 passthrough output spdif.
I tried all the firmwares, all kodi 's versions, no one solution...
Shame on you Tcl, it s the same problem with all ep680, ep640 series
The only Way is a Xiaomi mi box on hdmi input......

Have anyone tested the V270 Brazilian version (root version) ?

Change the transmitter

Also have this problem. 288. IPTV crashes the player. After some investigation it looks like TCL doesn’t use Exoplayer but one of their own.
Tried every possible IPTV app, all of them makes it crash the tv or when it works only have sounds or image stutters

Puksom said:
Also have this problem. 288. IPTV crashes the player. After some investigation it looks like TCL doesn’t use Exoplayer but one of their own.
Tried every possible IPTV app, all of them makes it crash the tv or when it works only have sounds or image stutters
Click to expand...
Click to collapse
Thank's. The TCL application is named "com.tcl..ui_MediaCenter".

I've been trying to solve the same problem. So annoying...
The best progress I did was installing Nova Player. It has a mode for passthrough that correctly send DD and DTS to my receiver if I set the TV (50ep640) to PCM on the audio output setting. Mode 1 is the one that works.
I don't know if Kodi or Mx player could support the same.
On Nova Video Player, two audio passthrough modes are supported:
Mode 1 (almost deprecated) targets TV boxes with early versions of Android (up to Kitkat 4.4). Note that on some devices you need to set the sound volume to maximum (so that the streams are not altered by the sound mixer). This mode does a software SPDIF encapsulation with ffmpeg .
Mode 2 targets latest versions of Android above 5.1 (Nvidia Shield TV and Android TVs) using official Android framework support.

fjrdomingues said:
I've been trying to solve the same problem. So annoying...
The best progress I did was installing Nova Player. It has a mode for passthrough that correctly send DD and DTS to my receiver if I set the TV (50ep640) to PCM on the audio output setting. Mode 1 is the one that works.
I don't know if Kodi or Mx player could support the same.
On Nova Video Player, two audio passthrough modes are supported:
Mode 1 (almost deprecated) targets TV boxes with early versions of Android (up to Kitkat 4.4). Note that on some devices you need to set the sound volume to maximum (so that the streams are not altered by the sound mixer). This mode does a software SPDIF encapsulation with ffmpeg .
Mode 2 targets latest versions of Android above 5.1 (Nvidia Shield TV and Android TVs) using official Android framework support.
Click to expand...
Click to collapse
Thank's. I've tried Nova Player with its 2 modes but it doesn't work at home.
Mode 1 => Video OK, sound looks like a machine gun
Mode 2 => Video freezes, no sound
I've tried these 2 options with the audio TV setting on PCM, auto, Passthrough.

Shield 2019: Enabling audio passthrough using USB audio protocol UAC2

I have the newest model Shield I believe:
Android ver. 9
SW version: 8.2.2(32.6.509.0)
Kernel ver: 4.9.140-tegra ...
Description: Tegra X1 + mDarcy
While there is audio passthrough via HDMI, USB audio output fixes the bitrate at 16/48 or 16/192 in high quality mode. I have a semi high-end hi-fi setup with good DAC where you want an 'untouched' audio bitrate and 24 to 16 bit downsampling is rather unattractive . I have been looking at: https://source.android.com/devices/audio/usb It appears that using isochronous mode is universally standard, but the sub mode on most Android devices, including the Shield, is set to Adaptive when it needs to be Asynchronous sub mode to do this. I can't find any online source with an kernel mode setting to do this. I am not even sure I am on the right path here.
Any insights, references, tips, or better yet some ADB command line code?
Thanks,
p-we

Hi there - where did you land on this? Thanks!

Never took off...

p-we said:
Never took off...
Click to expand...
Click to collapse
Still no take-off or did you manage something with this? I'm in the exact same hi-fi boat
I did find that sideloading UAPP (USB Audio Player Pro, will cost you 8 dollars or so) on the shield technically works and it can play audio without any re-sampling done (my dac shows the sample rate changing when songs have different sample rates so I know it works), even stream from Qobuz / Tidal, but the UX is pretty much unusable since it's not an Android TV app lol

binasnotatie said:
Still no take-off or did you manage something with this? I'm in the exact same hi-fi boat
I did find that sideloading UAPP (USB Audio Player Pro, will cost you 8 dollars or so) on the shield technically works and it can play audio without any re-sampling done (my dac shows the sample rate changing when songs have different sample rates so I know it works), even stream from Qobuz / Tidal, but the UX is pretty much unusable since it's not an Android TV app lol
Click to expand...
Click to collapse
I've not looked into the USB sub mode since I first looked into it and posted in 2021.
Good idea on UAPP which I am familiar with USB-C on android mobile. Might play around with that as I think I'm already good for the $8. It's indeed a pain when Android apps don't use the Google/Android TV remote system.
I've since solved the problem for my hi-fi audio purity 'fix' by moving to Roon which provides flawless high res audio (via network to an RPi's USB 2.0 audio output) and is controlled by mobile phone via the Roon Remote app. Now if Roon would only make an Android TV compatible remote app the Nvidia Shield would be a great UI experience and the USB output wouldn't matter anymore.

So for what it's worth, over at the Nvidia forums one of the staff members confirmed that this is on their 'to-do-list' so with a bit of luck we can see this fixed in the next Shield update
https://www.nvidia.com/en-us/geforce/forums/shield-tv/9/520414/match-content-audio-resolution-for-usb-audio/3359083/