[PROBLEM] No sound with bluetooth input after adding codec

[Tim Curtis]

Lip sync compensation typically has to be done in the source player via some option to set +/- audio delay in milliseconds. I've never seen it done in the Bluetooth receiving device.

[TheOldPresbyope]

@harrypulvirenti

So I built the AAC and aptX/aptX-HD codecs and rebuilt bluez-alsa (aka bluealsa).

The result works with either my Apple iPad or my Android Pixel 3A as BT source and Pi Headphone jack as MPD output device. This on an RPi4B running moOde 7.4.1 and using onboard BT transceiver.

In the case of the Pixel 3A,

Code:

pi@rpi4b2:~ $ bluealsa -h
...
Available BT profiles:
 - a2dp-source    Advanced Audio Source (aptX-HD, aptX, AAC, SBC)
 - a2dp-sink    Advanced Audio Sink (aptX-HD, aptX, AAC, SBC)


pi@rpi4b2:~ $ sudo bluealsa-aplay -L
bluealsa:SRV=org.bluealsa,DEV=58:CB:52:90:F0:74,PROFILE=a2dp
   Pixel 3a, phone, capture
   A2DP (aptX-HD): S24_LE 2 channels 48000 Hz

As you can see, the Pixel and moOde negotiated the aptX-HD codec.

At this point, I don't know what is causing your issue.

Regards,
Kent

PS - You didn't say if your lip-sync problem is audio-lead or audio-lag. I'm supposing you're experiencing audio-lag and hoping that using one of these "advanced" BT audio codecs might result in less of a lag. Since they are implemented in software I suspect this is a vain hope. If the audio lags the video, then the usual solution is to retard the video on the source side.