BT output: Only white noise when playing local files or internet radio

General
1

As described in https://github.com/mopidy/mopidy/issues/1411:
Mopidy installed, on Raspi Model B, audio output via Bluetooth dongle, the Spotify plugin is working,
but when I try to play local MP3 files or any stream from the streams page of the musicbox_webclient, it is only white noise.

OTOH, internet radio streaming from the command line using
mplayer -ao alsa:device=philipsbt http://1live-diggi.akacast.akamaistream.net/7/965/119435/v1/gnl.akacast.akamaistream.net/1live-diggi
is working fine.

This is my /etc/asound.conf (note: I edited the file without actually understanding it):

pcm.mmap0 {
type mmap_emul;
slave {
pcm "hw:0,0";
}
}

pcm.philipsbt {
type plug
slave {
pcm {
type bluetooth
device 0C:A6:94:3D:6D:CA
profile "auto"
}

}

hint {
show on
description "BT Headset PhilipsBT"
}

}

ctl.philipsbt {
type bluetooth
}

pcm.!default {
type plug;
slave {
pcm philipsbt;
}
}

ctl.!default {
type plug;
slave {
ctl philipsbt;
}
}

Is this an ALSA configuration issue? I’m out of ideas.

2

To answer my own question:

I had to change the output configuration in mopidy.conf:

[audio]
# output = alsasink
output = sbcenc ! a2dpsink device=philipsbt

I found an important hint in one of liamw9534’s comment on https://github.com/mopidy/mopidy/issues/705