[mythtv-users] Horrible Audio Problems on Video Glitch

[George Mari]

Bryan Murphy wrote:
> Hey guys, I just recently traded in my Hauppage PVR-350 for a pcHDTV
> 5500.  I live in the Chicago Metro area, so my reception ranges from
> good to pretty lousy, but in general I get a passable signal on every
> channel but our local CBS affiliate (channel 2).
> 
> The problem is, whenever there's a glitch in the video stream, I get
> VERY VERY LOUD popping and screeching noises.   Now, I can handle
> audio and video glitches, but these noises are simply out of control.
> They are irritating, they hurt my ears, they annoy other people
> watching the TV, they startle the dogs, and I'm afraid they might even
> damage my audio system.
> 
> I've tried a bunch of things, and I simply don't know what to do at
> this point.  My computer is certainly capable of handling the audio
> and video stream.  I use mpstat/dstat/iostat to monitor my load level,
> and I'm using maybe 40% of my CPU and reading and writing about 6 to 8
> megabytes per second to/from the disk drive.
> 
> Given that I live in the middle of the city, on the first floor, and
> am surrounded by tall buildings, I have little hope of enhancing my
> signal to the point where this isn't a problem.  As I said earlier, I
> can deal with the glitches, but I really really wish the audio dropped
> out instead of screeching.
> 
> Can anybody please help me?  I'm at my wit's end over this.
> 

1. Are the noises limited to only certain channels?  Or do they appear 
on pretty much any channel you happen to have gotten a glitch in?

2. What happens if you play back one of the affected recordings using 
different software, like mplayer?  Do you still get the popping and 
screeching?

3. Are the noises embedded in the recording itself, or is you sound 
system just reacting to a possible lack of audio in the stream this way? 
  To test this, try playing back one of the affected recordings in slow 
motion and see if the noises are also in slow motion.  If they aren't 
embedding in the recording, try to figure out what part of your PC's 
sound system is causing the problem.

4. Another way to test this is to playback one of the affected 
recordings on another computer.  Do you still get the awful noises, or 
something more benign?

As others have stated, you can reduce the dropouts and glitches by 
possibly improving your antenna setup.  If you haven't already, checkout 
the Chicago OTA thread on avsforum.com for loads of good info on what 
antenna is good for your particular location and building.