[mythtv] [INFO] Getting the most out of your SAA7134 chip

[Martin Moeller]

Could this information be included in the mythtv troubleshooting
section? I am pretty sure that others have or will have this issue at
some point.

INFO:
-----
After a couple of days of troubleshooting on the video4linux mailinglist
I have now gotten rid of the occasional (and sometimes more than that) 
static (white noise) sound upon channel change.

I also used to have background noise on my (now stereo) recordings, 
which I got solved using the latest video4linux snapshot from
http://linux.bytesex.org. Getting the latest xawtv snapshot is also 
a good idea (if for nothing else then for the updated v4lctl command).

On SuSE the drives for the saa7134 card are located at
kernel/drivers/media/video.
If you install the video4linux snapshot it places drivers in v4l2 in
stead. 
Therefore: Remove those (if you have them) before installing the
snapshot (might want to make a backup, though). *KEEP* the videodev.[k]o
file as the video4linux snapshot does not include this.

Use the following settings for the saa7134 related modules:

options tuner pal=b
options tda9887 qss=1 port2=0
options saa7134 oss=1 dsp_nr=1 mixer_nr=1 oss_rate=32000

The tda9887 options are key here. I know for sure it helps a lot on
Medion7134. How much it helps on other saa7134 chips you will have to
tell me. Of course you shouldn't set 'pal=b' unless you use the
'PAL-B/G' standard. Other values are described in the doc/ directory of
the video4linux snapshop in the file insmod-options.

In the 'channel' table there is a field called 'tvformat'. If you set
this to the exact standard you use (in my case 'PAL-BG') you should be
absolutely sure to avoid static in the future (maybe even without the
latest drivers). This may or may not help for other capture cards than
saa7134 and its close relatives (saa713x), but for me it has resulted in
crisp, clear stereo sound and who wouldn't want that :)

-- 
Martin Moeller <martin at martinm-76.dk>