dTV sound unrelated to input choice  

I searched under dTV sound problems in this forum but could not find my problem.

1)Under the original software WinTV2000 (in windows 2000)of the Hauppage WinTV + FMradio and an external cable from WinTVline out to SBLive line in, there is no sound problem.
2) I played with the sound settings of dTV a couple of days (vs. 2,1,2,0)to no avail to get rid of the unpredictable on and off of the sound.
3) Under settings/audio input i can choose for tuner, MSP/radio, internal, external and have this on and off sound . If there is sound it is for between 3 seconds and mostly 2 minutes. When it disappears it is gone for at least 20 sec up to 5 minutes. There is no fading. It is abruptly there and snaps of that way.
4)In finding the stations I had to copy the freqs found by WinTV to Cannel.txt of dTV.exe as the Dutch cable (Casema) freqs do not equal those in the list
5) However I do not know what to fill in for: ChannelLow=
ChannelHigh= So I just picked 1 for low and 69 without knowing the(sound?)consequenses
6) When I start up dTV very briefly I can see a list flowing by that checks the hardware and found no error messages.
7) Under Hardware/Hardware info it finds BT-Typ BT878, a tuner and a MSP radio version msp34255D-B31

What can I do?
I love the deinterlacing I need to project the image with a D-ILA G11
Kyrill
Teh PC has an AMD thunderbird 850, 256 mb Sdram and a SBLive

Hi Phat..

You are welcome. It is not calibrated yet except for what Dilard could offer until now: The Black wizard and the Phase wizard. I still need gamma callibration and colour. However it is already "impressive" on a thin bedsheet. Next week I have my screen (much too big, I realize now). After that is setup I will email you for an invitation

But your solution with the external tuner, how does that help you in enjoying dTV deinterlacing?

Hi
No one yet who has met this problem with dTV?

I suspect that the sound is "snapped" off as if the radio carries become to weak and static noise would interfere. Just as it happens with the fm radio. Suddenly the station is gone instead of hearing it through the noise. I think so, because when I do hear the sound I hear how mono and stereo flips, as I have put stereo under MSP/radio on "automatic adjustment" This suggest to me that the signal strenght varies. This is strange because I have cable and it does not happen with WinTV, So I have no idea what dTV is doing to get the sound. It does not seem to accept external only, what I think it should do(?) as the WinTV uses an external loop cable to the line in input of the soundcard.
Anybody who has suggestions?
Kyrill
PS
What ever audio input I choose, I always see TV terrestial +PAL+BG etc. as if I have only choosen for MSP/radio
Kyrill