Comment # 24 on bug 967156 from Takashi Iwai

Then the question is whether the device really works before replug or it's
wrongly configured by some reason.  Try to boot in runlevel 3, then login there
on Linux console, so that no PulseAudio is running.   Does "aplay -Dhw:0
somefile.wav" work?  (it assumes the first card is USB one.)