[mythtv-users] Echo on TV Sound

[J. Donavan Stanley]

Christian Fridgen wrote:

> Hello,
> finally i switched my sound output from the crappy debugging 
> mini-pc-speaker to some good speakers to check sound quality and 
> discoverd a 'inverse' echo when watching TV.
> I hear the live TV sound at a very low volume and with about 2s Delay 
> the normal sound matching the picture in normal volume.
> How can i get rid of this noise. I tried muting the line-in, but when 
> i do that i also loose normal sound after this two seconds delay.
> I switched to ALSA some time ago, as my MSI board with an Intel ICH5 
> chipset with CMI chip, using AC97 Codec was not able to do volume 
> control for PCM with OSS (it also isnt able todo this with ALSA too). 
> Currently I'm using line out, but i will try SPDIFF very soon to, just 
> don't have a decoder here at the moment, so i cant try whether this 
> will be gone then...but I doubt it.
> Can anyone tell me how to set up alsamixer to remove this echo or can 
> this be set somewhere in Mythtv to do no live-output from line-in? 
> There are plenty of different channels to set, but excpet main, 
> line-in and IEC958 Capture none of them seems to do anything.
> BTW; now as I know there is this echo, I can even use the crappy boxes 
> again and hear it, it was just to low volume to recognize this before.


You need captured turned on for line in and you need line in muted.