[ivtv-users] Sound died on hvr-1600

[Dale Pontius]

On 06/12/10 08:42, Andy Walls wrote:
> On Fri, 2010-06-11 at 22:03 -0400, Dale Pontius wrote:
>> On 06/10/10 23:14, Andy Walls wrote:
> 
>> Thanks for all of the thought, but last night/today/just-now I think I
>> shot any theories full of holes.
>>
>> The weather has been warming today, but last night I shut the computer
>> down.  Regular shutdown, not full power-off, so 5VSB was still on, which
>> is at least significant to the red-screen.  This morning, in the cold, I
>> powered on - no audio.  A little later I rebooted, still no audio.
>>
>> So much for it being largely about temperature.
>>
>> It has warmed quite a bit today, and this evening I had a few minutes,
>> so I removed all of the modules, then modprobed cx18 and cx18-alsa.  I
>> have sound, again.
>>
>> It's just flakey.  Maybe when I get a break and take this system down, a
>> bit of dust-off and reseating cards will work wonders.
> 
> Well, some things to try:
> 
> 1.  remove all instances of the cx18-alsa.ko module from
> under /lib/modules.  It shouldn't matter, but most users never need it,
> If hald or pulseaudio has it open, you may be unable to switch away from
> 48 ksps and then back.

My kernel is getting a little long in the tooth, so it wouldn't hurt me
at some point to build a new one.  2.6.33 seemed a bit disruptive to
lirc, but I think that's worked around by now.

Do I even need cx18-alsa?  I sort of built it because it was there and I
have a cx18, even though I never needed it before.  What is cx18-alsa
for, anyway?
> 
> 2. When you have no audio, try using v4l2-ctl to switch from the tuner
> audio to line in audio and back.  You could also stop then capture,
> switch to 44.1 ksps or 32 ksps and then restart the capture.

I'll give that a shot.  I've no doubt I'll get the opportunity.  I'm
pleased enough that the unload/reload worked, because nothing else has
so far.  I don't know if it "worked" or if it was just luck, like
booting occasionally is.
> 
> 
> 
>> I had been focusing on initialization, partly because when we're
>> analyzing, we analyze the major modes of operation practically to death,
>> especially the performance-critical ones.  There are things you can do
>> to simulate end-of-life device shifts, etc, and we do those.  For the
>> power circuitry you analyze power-up to death, too.  But initialization
>> is one of those typically non-critical things that you logically verify.
> 
> Whenever I see
> 
> 	Verification method: inspection
> 
> in a design review, my internal alarm bells go off.

When I said "logically verify" I meant logical simulation, as opposed to
full multi-corner analog transistor-level simulation.  I don't trust
"inspection" either.  (There are those other phrases, "correct by
design" and "correct by construction.")

Dale