I use the TBS dual tuner card 6981 in combination with DVBLink TV Source and Windows Media Center (x64). Unfortunately, I have some trouble with one of the tuners. The DVB stream which is transfered to Windows Media Center is corrupt most of the times. I can see app. one fifth of the picture (starting from the top) and all picture data below is missing. Also, the audio stream seems to be broken. This happens on both SD and HD channels.
Then, sometimes I can record two separate HD or mixed SD / HD streams at the same time without any problem.
What I tried yet:
1.) Tested different card drivers from 18.104.22.168 to 22.214.171.124 -> No difference.
2.) Exchanged the satellite antenna cables between the tuners -> No difference, DVBLink server reports signal quality above 90% for both tuners.
3.) Connected the tuner card with or without additional power supply -> No difference.
4.) Tried to avoid IRQ sharing in Windows 7 device manager by disabling other devices in BIOS -> No difference.
Do you have an idea what could cause this issue or what I should try to solve it?
Or maybe my tuner card is defective? What do you think?