Hey All,

I'm having a problem with mythtv (or ivtv?) in that when I'm watching livetv, or a recorded show if the screen happened to go dark, or black the sound is very choppy. Also, this happens when the screen is all white as well.. some comercials have that.

Aside from that, it works perfect during a show.. just when the lights go out, its nighttime on the tv show or whatever i can't hear a thing. Anybody know why this happens? I've tried lowering that 'NTSC Signal Threshold' in the settings, that didn't work. It really seems like a threshold of sorts, because when the picture is bright the sound is perfect

Thanks in advance

R4V5
kernel: ivtv: version 0.2.0 (rc3j)
NVIDIA-Linux-x86-1.0-7174
dma is on
and like i said, works perfect except for this little sound problem

This sounds stupid, but have you tried rearranging the cables to eliminate cross talk? If I'm not careful about cable placement I get strange crackling sounds from the speakers when there's a lot of text or other regular patterns on the screen.

i'm a big believe its always something stupid, starting with wiring for most things. in this case, its not crossed cables, i'm fairly certain. they are also pretty well insulated cables. i've been noticing it more lately in a few scenarions.
black screen with sound .. the sound gets buggered up
white screen with sound
actually, any "one" colour on the screen causes weird sound breakups.
green, blue, whatever..normal tv programs are great, but anything with a lot of dark in it like Kill Bill for example (even that black and white scene at the start gives me problems), and ONLY on live tv, playback of a mpeg file, or divx i've 'backed up' is fine.

then magically, as soon as the picture has more colours, and brightens up.. sound is perfect again

try searching the forums I seem to remember this. For some reason in my mind it's associated with pvr350 though. It will be a rather old post if you can find it.

_________________
Have a question search the forum and have a look at the KnoppMythWiki.

Xsecrets

I have this EXACT same problem! I have a PVR250.
Ever fix it?

i'm searching old threads as mentioned above, but yeah, no luck yet!
i'll be sure to post when a resolution is found

just trying to keep the thread alive.. anybody have any clues/suggestions?

My MythTV box has been packed up for a while now due to my recent move, so I haven't been able to investigate this problem. It happened EXACTLY as described though. Anytime the TV showed a very bright or dark screen, usually of a similar color, the sound stutters badly. E.g., sound stutters when a TV show would fade out to black or white. If a bomb went off on a TV show and the screen gets really bright the sound stutters, etc.

Maybe it would help if I posted my specs, as best as I remember them:
Athlon 2400+ CPU, Knoppmyth R4V5, GForce 3 for TV-out, PVR250 (the model that comes with the latest gray remote), SB Live sound card, 1 gig of RAM, 40 gig HDD, I forgot the mobo type.

Try enabling "extra audio buffering" under
Setup -> TV Settings -> Playback

I've had it enabled for a number of days, and I haven't noticed the sound problem since I've enabled the extra buffering.

Thanks for the help!

I'll try as soon as I get the computer set up again. Thanks!

Odd how it is linked to certain video patterns though...

I'm having a similar issue. When a movie or tv show gets dark, my video and sound slows down and sometimes freezes. This happens with live tv and recorded video. I thought it might be something to do with commercial flagging but I tried different settings to no avail.

I'm running KnoppMyth RA15.1 with a PVR 250 and NVIDIA 5500. It's running on a Shuttle with over half a gig of memory and a 2.4Ghz P4.

Any suggestions?

Did you try the extra audio buffering setting listed above?

-brendan

I just enabled it. I'll see what happens.

Thanks.

Just an update that fixed the problem.