Hi, Some of you are aware that I've been re-engineering the Minster Bells and Music Player at Wimborne Mode Town. Amongst other things I split the functionality into two Pis (the original Pi 3 and a Pi Zero); both are equipped with an Adafruit Stereo 3 W Amplifier Bonnet:
https://thepihut.com/products/adafruit-i2s-3w-stereo-speaker-bonnet-for-raspberry-pi The Pi 3 takes care of the music that plays in the Nave and I configured that first and using a cut-down version of the original code, it has been running satisfactorily for a week or two. I then backed up its SD Card and created a new one using the Music Player image as a starting point. Again, using a cut-down version of the original code installed on the pi Zero, I have now got the bells to ring (almost) perfectly. The one problem that I have is the volume setting command. In both programs I have a line: subprocess.call(['amixer', '-c', '0', 'set', 'PCM', 'playback', nave_vol]) In the music program this works perfectly every time, but in the bells program it fails intermittently with: amixer: Invalid command! After this failure alsamixer has no control over the volume level. However, once the amixer command is working so is alsamixer. Any ideas on what I should check? AFAIK there is no difference between the two devices other than the underlying Pi type. I've tried all sorts of combinations of amixer command from the man page, but when it works it works and when it doesn't it seems to refuse to do anything. -- Terry Coles -- Next meeting: Online, Jitsi, Tuesday, 2020-01-05 20:00 Check to whom you are replying Meetings, mailing list, IRC, ... http://dorset.lug.org.uk New thread, don't hijack: mailto:dorset@mailman.lug.org.uk
