Subject: [mythtv-users] audio hiss

[Gregory J. McGee]

Try the oss driver. (i810_audio) I had to for the same reason,
amongst others. (FIC AU11 in use here (NF2)) 

I had fits with ALSA, used it for a long time, but never could quite get
it right with myth on my board. .

I even bought a "Hercules Muse LT" (cmipci), but its noise was 2x as
bad.(output is clean... recording sucks---hissssssssss) I may try to use
it for surround output, and it's digital out probably works.
Right now it's taking up a slot probably destined for a PVR250 or m179.

If you are using anything but Debian, just comment out anything alsa
related in modules.conf or modprobe.conf (2.4/2.6 depending) and
/etc/modules if your distro uses it, (also remember modprobe.preload)

(I never managed to grok Debians module config setup. I punted and
installed Mandrake Cooker and was fully up and watching recordings in ~1
hour after all the practice I had attempting to get Myth working right
in Debian/Knoppmyth. Most of that hour was downloading and xmltv sync
time.)

Load i810_audio by whatever means, install aumix, and mute as
appropriate, it will actually use and reload your settings on restart...
(Not reliable with ALSA from what I saw)

Also make sure any unused inputs (cdrom/aux/mic) are muted, I get noise
from a busy HD if CD input gets left on.
 
> Date: Sat, 27 Mar 2004 15:30:58 -0600
> From: Mark Staggs <me at markstaggs.net>
> Subject: [mythtv-users] audio hiss
> To: mythtv-users at mythtv.org
> Message-ID: <4065F292.8050700 at markstaggs.net>
> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
> 
> I'm using an Biostar nforce2 mobo and a cheap Pinnacle tuner (bt878). 
> I'm getting a high-pitched hissing noise on some (not all) channels. 
> If 
> I check through xawtv, the sound is absolutely fine on those same 
> channels.  I tried modifying the sampling rate in the setup, but that 
> didn't appear to make a difference.  I also tried modifying the
> line-in 
> and capture levels via alsamixer, but the hiss remained.  If it helps,
> I'm using ALSA with kernel 2.6.4,  and mythtv 0.14 on Gentoo.  If 
> there's no obvious fix, would trying a different soundcard be 
> worthwhile?  I'm not sure where exactly the culprit is.  I've used
> this 
> tuner card in other boxes running MythTV w/o any problems.
> 
> -- Mark
> 
-- 
Gregory J. McGee <gjmcgee at cableone.net>