hmm, ok ive done more mucking around than i care to mention. Firstly, everything so far seems to point to an IRQ issue. When using the FusionHDTV app, I get about ~28% CPU usage while watching OTA HD using UVD as the decoder, yet the picture is incredibly jumpy. Deinterlacing looks great, as does pic quality on still images, but as soon as there is movement (particularly in sports) the picture goes very jumpy - makes it painful to watch, and definately unacceptable.
Now ive tried the card in all 3 PCI slots with no improvement. The DualDigital2 installs itself as a VIA USB Hub and 2 other VIA USB related things (will post exact names and pics when i get home tonight). The 2 tuners come up as USB devices. No matter which slot i put the capture card in, the video card is always sharing an IRQ with one of the 3 installed devices from the capture card.
Now i noticed that I could disable 2 of the 3 installed devices and still use the tuners but the 3rd one stopped the tuners from working (i think the one that is required is called VIA USB Root Hub and the other 2 were something similar - again will post details when i get home from work). Also at this point in time ive disabled like... everything that isnt required (COM ports, Serial ports etc.).
So i convert my PC from APCI Uniprocess to playin APCI. Now at least I have a proper IRQ listing (i think). Now i disable the Via Root Usb device and reenable it and it gets assigned a new (unique) IRQ under device manager, however the problem is still there when i try load up FusionHDTV. Im guessing that perhaps the device hasn't reallly been assigned a new IRQ because this is actually done by the BIOS during boot ? Unfortunately my Motherboard doesnt provide much in the way of PCI management.
Anyway, things to do this afternoon after work:
- Install MediaPortal and verify that the problem isnt just in FusionHDTV software.
- Flash mobo to latest BIOS and see if i can get any more control over IRQ assignments to PCI slots.
- Download demo files and see if playback stutter occurs there.
- Worst case scenario, reformat (again) and install Windows as Standard PC. I tried to convert to standard PC last time, but while i could still boot, all my USB function disappeared (including my mouse :P).
- failing above 4 steps, kill self. :P
If anyone has any ideas, feel free to post. I will update this thread tonight with any more info i get.