Audio over Stereo Connectors

The release notes of the latest software say:

New Features in this release (CAF tag: LA.BR.1.2.4-01810-8x16.0) compared to June release (Caf tag: LA.BR.1.2.4-00310-8x16-1)

Audio over Stereo connectors
Needs stereo connector soldered to J7 and mixer settings changed in SW

I understand the connections on J7 from the documentation and schematic, but how do I change the mixer settings in the software? I have been tracing through the source code but I’m hoping someone can give me a pointer.

I copied the headphones settings into the hdmi sections of mixer_paths_sbc.xml and got audio out on my headphones…but it sounded a bit crackly and then the TV turned blue and the sound got stuck. I had to power cycle the board.

I reverted the mixer_paths_sbc.xml file and instead change the audio_policy.conf to set


I now get full volume audio on the headphones for a few seconds, although it is crackly, and then it drops dramatically so that I can barely hear it, even at full volume.

I tried also to change the audio_policy.conf but I get read only error:

sudo adb -s b6ca2e78 push audio_policy.conf /system/etc/audio_policy.conf
adb server is out of date.  killing...
* daemon started successfully *
failed to copy 'audio_policy.conf' to '/system/etc/audio_policy.conf': Read-only file system

I haven’t had a chance to test this, but the Audio App note here gives some direction on how to route audio to the headset jack under Android by using tinymix commands. Have you tried tinymix yet?

Hi @andrewn,
Did you get it working?