Sound not working on 3.12.x and 3.13.x kernels for Fedora 20

[Tim]

On Tue, 2014-04-29 at 13:49 -0500, dwoody1 wrote:
> I installed F20 shortly after it's release. Everything worked as
> expected. All kernels released since then have resulted in the sound
> not working.
>  
> The kernel that works is 3.11.10-301.fc20.i686+PAE. Sound does not
> work for the 3.12.x and 3.13.x kernels.

I installed it about a week or two ago, but had no speakers connected at
the time.  These are the currently installed kernels, I haven't tried
sound with the older one, yet:

[tim at troubled ~]$ rpm -q kernel
kernel-3.11.10-301.fc20.i686
kernel-3.13.10-200.fc20.i686

I have sound, but it's too quiet - it's down by about 15dB, according to
my sound mixer (a real audio mixer, that my computer is patched into),
from where I expect it to be (based on prior experience).  And my
cabling is fine (my background is in electronics engineering, I have
thoroughly checked the cabling and equipment).

The pulseaudio metering is also showing very low, for audio sources that
I know have plenty of signal strength.  Running the computer's audio
mixer levels into the overdrive range only manages to bring audio levels
up by a small amount - normally you'd get horrid distortions as you go
just a bit above 100%.

I did have one application play at proper levels, once, but everything
else is running low.

The alsamixer levels have been turned up to full, as well as the
pulseaudio controls (master levels, front speaker levels, headphone
levels, and PCM/wave output).

There does seem to be some software bugs, you seem to be suffering worse
than I am, though.

-- 
tim at localhost ~]$ uname -rsvp

Linux 3.13.10-200.fc20.i686 #1 SMP Mon Apr 14 21:00:56 UTC 2014 i686

All mail to my mailbox is automatically deleted, there is no point trying
to privately email me, I will only read messages posted to the public lists.

George Orwell's '1984' was supposed to be a warning against tyranny, not
a set of instructions for supposedly democratic governments.