Hi,
I’ve seen this other topic, but that didn’t seem to work for me.
Set-up:
- Raspberry Pi Zero W (Jessie 4.9)
- pHAT DAC (Pimoroni standard install)
I’m just streaming a single internet radio channel using mpd (and mpc directly in the command line) and that works fine for stereo. However I’m going to build this into an old radio with a single speaker, so I’d like to mix the stereo to mono. And I’d prefer to do it in software rather than hardware, just to be elegant… :)
I tried changing /etc/asound.conf to the following (as described in this post):
pcm.card0 {
type hw
card 0
}
ctl.card0 {
type hw
card 0
}
pcm.monocard {
slave.pcm card0
slave.channels 2
type route
ttable {
# Copy both input channels to output channel 0 (Left).
0.0 0.5
1.0 0.5
# Send nothing to output channel 1 (Right).
0.1 0
1.1 0
}
}
ctl.monocard {
type hw
card 0
}
pcm.!default monocard
ctl.!default monocard
But after a reboot I get no audio at all and the mpc and mpc stop commands are met with "ERROR: Failed to open audio output".
The only /etc/asound.conf that produces audio for me is the Pimoroni pHAT DAC standard one of…
pcm.!default {
type hw card 0
}
ctl.!default {
type hw card 0
}
…which doesn’t do any stereo->mono mixing.
Any ideas?