I'm running Stretch on an RPi 3 B+. I have a C-Media USB sound card showing up as:
card 1: Device [USB Audio Device], device 0: USB Audio [USB Audio]
and ALSA recognises it as the default card
speaker-test -c2
plays sound through the card , no problem, as does
speaker-test -Dhw:1 -c2
But trying to start jackd (jackdmp version 1.9.11) with
jackd -P75 -dalsa -dhw:1 -p1024 -n3 -s -r44100
gives the following error:
ALSA: poll time out, polled for 34828042 usecs
JackAudioDriver::ProcessAsync: read error, stopping...
Any ideas as to how to get jackd working on the 3 B+ ?