Quoting Raymond Yau (superquad.vortex2@gmail.com):
After upgrading from 3.16.0-38-generic (Ubuntu Utopic) to 3.19.0-18-generic (Ubuntu Vivid) my audio stopped working. The issue appears to be in the snd-hda-intel driver.
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HDMI fail because drm/i915 fail
So it appears. I hadn't noticed these: | [000d00h02m01s] Could not create debugfs 'i915_pipe_update_start' directory | [000d00h02m01s] snd_hda_intel 0000:00:03.0: Cannot turn on display power on i915
| ALSA lib pcm_pulse.c:752:(pulse_prepare) PulseAudio: Unable to create stream: No such entity
This seem pulseaudio fail
Yes. This error is because PulseAudio is also unable to communicate with the soundcard while 3.19 is running. However, the issue at hand is not PulseAudio related. Even with no Pulse running, aplay and friends fail to work the card.
Thnx, -Sndr