[mythtv-users] Audio squealing and hissing

[William Munson]

Christopher McCurdy wrote:
> My mythtv backend has a WinTV-Go for recording. Up until a month ago, 
> I was using RCA video output from my directv receiver plugged into the 
> composite input, and the RCA outputs from the satellite receiver 
> combined into a stereo plug and plugged into the line-in slot on the 
> card. Sound was fine, a little tinny, but it worked well enough. From 
> there, I daisy-chained the line-out of the WinTV card to the line-in 
> on my motherboard (snd_cmipci). Everything was good.
>
> But now I'm using the coax cable as the input. The sound works, but it 
> produces a horrible squeal louder than the program's audio, and 
> sometimes it just distorts things. I've heard some things come out 
> octaves lower than they should be, but sometimes there is just buzzing 
> and cracking... always louder than the program's audio.
>
I am not an expert on this but from what I understand, If you use the 
coax input then you are using the audio decoder built into the capture 
card. This audio is generally carried over the pci bus. You also have a 
jumper between the WinTV and the sound card which duplicates the audio 
path and creates the echo. Try removing that cable, you may find it 
still works.

Good luck,
Bill