problems with AverMedia Stereo

["Robert W. Fuller" <microbus@xxxxxxxxxxx>]

I'm not sure this is the right place to post about this, but I'm sure 
you can point me in the right direction if it isn't.  I have a couple of 
annoying problems doing capture with the AverMedia Stereo, bttv, and 
v4l.  I'm either going to solve them, or return the card to Gateway for 
a restocking fee (Their return policy states something about you paying 
for shipping and "handling."  When you call them, their offshore 
customer service representatives politely explain that the 10% 
restocking fee that isn't mentioned in their return policy is the 
"handling" fee.  Thanks Gateway!  I'm not bitter, and I'm sure I'll 
order again soon.)

Under Linux for whatever reason, I get noise from the audio loopback. 
This isn't true for Win2K (Note that I'm not a Windows user 
anymore--thanks to OpenOffice, Mozilla, VLC, GAIM, and others--but I use 
Windows as a control for hardware that the vendor supports on Windows 
before I try to get that hardware working under Linux.)

The other problem I'm having with the board occurs when I do a full 
frame NTSC capture, 720x480@xxxxx fps.  I get a narrow intermittent 
horizontal line approximately 1/3 from the bottom of the frames.  I 
don't see this when I'm viewing the full 720x480 frame on the Windows 
side of things.  Also, I found that I could remove this line by running 
yuvdenoise with the de-interlace option.  However, the video is already 
"de-interlaced."  Consequently, running the de-interlacing filter has 
the nasty side effect of making the capture blurrier.

Will I have better luck with a different BT878 board?  Perhaps I should 
use something completely different?  Are people familiar with these 
problems?  Are there known solutions?

On a side note, I'm very pleased with Linux 2.4.x performance for doing 
raw video capture.  Capturing full frame NTSC video raw, according to 
vmstat, I'm getting a sustained 20 MB/sec to my 5400 RPM hard drive.  A 
gigabyte per minute is just fine with the Linux disk subsystem (contrast 
that with Win2K which chokes around a few megabytes per second.)