After a fresh reboot, the sound works ok but if I put the computer to sleep (pm-suspend), after it wakes up there is no sound anymore.
I did try 'alsa force-reload' after suspend but still no sound. After 'pm-hibernate' sound is back again.
I found an old thread here: https://bugzilla.kernel.org/show_bug.cgi?id=49421 where Michael seems to have the same problem which is still unsolved; maybe I can help with more info.
I attached the 'alsa-info.sh' output before and after suspend: 'alsa-info.txt.before' and 'alsa-info.txt.after' (as a patch to stay below 80k mail size rule: diff -u alsa-info.txt.before alsa-info.txt.after > alsa-info.txt.patch)
The only difference between before and after is this one: @@ -241,7 +241,7 @@ Node 0x11 [Audio Input] wcaps 0x10051b: Stereo Amp-In Amp-In caps: ofs=0x11, nsteps=0x2e, stepsize=0x03, mute=1 Amp-In vals: [0x12 0x12] - Converter: stream=4, channel=0 + Converter: stream=0, channel=0 SDI-Select: 0 PCM: rates [0x160]: 44100 48000 96000
The PC is here: http://www.dell.com/us/p/xps-27-2720-aio/pd?ref=PD_OC, but the 2y older version with no touch
If I boot into windows (8.1) everything works great, including sound (even after suspend)