I have recently built a mythtv box in the hopes of replacing my Dish Network Receivers. I have the following Hardware:
- AMD Sempron 3000+
- 1GB Corsair RAM
- 1 250GB Maxtor Drive
- 1 100GB Western Digital Drive
- MSI - Nvidia GForce 6200 w/128MB (Using SVIDEO out)
- Via 8237 on board sound ( no SPIDF Yet)
- 1 Hauppage PVR150 MCE capture card
- 1 Air2PC OTA Only (rev. 2) HDTV Card
- 1 Generic Brooktree Frame Grabber card (not currently in use)
- 1 DVD/CDRW Combo Drive (white box)
- 1 nmediapc 200B HTPC enclosure

Currently Running Knoppmyth R5C7
Nvidia driver version (8762)

Now here is the issue. I can watch TV from the Antenna on the PVR 150 without any issues using my HDTV set top antenna. I can watch DVD's without any issues. But when I watch, Live, or recorded HDTV programs, I get random Pauses. This can be resolved by hitting skip ahead or skip back, or by pressing and releasing the pause button. However it just happens again at another random moment. I get 6 Channels in my area, 8-1, 8-2, 33-1, 33-3, 43-1, 43-2. Now I have done the following with guidane from these forums:

Changed AGP from 8x to 4x in the bios
Disabled "De-Interlace"
Enabled "De-Interlace - Using BOB x2
Changed from "Standard" to "Xvmc"
Changed "Bob x2" to "Linear", "kernel"

I am out of Ideas, I have actually read in some of the forums about switching from the 6200 NV card to the 5200. I have also played with the thought in getting an ATI card, (shudders). I am at my wits end with this. In order to make the whole thing viable for my wife and kid, I need to get this resolved. I would like to get cable, however, I am not sure that this freezing would be resolved by this.

Any help, would be greatly appreciated. I am at the point where I will try anything.

Ok,
Last night I went home with full intent on making this whole thing work, here is what I did to make it happen.

I closed the mythfrontend, and launched the 'nvidia-settings' utility from the menu bar. (This can also be done by cli #nvidia-settings in an xterm.)
I removed the checks from all boxes related to "sync to vblank" I beleive there were 3. Quit the utility, and then relaunched the mythfrontend. After getting the frontend up, I went into "Utilities-Setup > Setup > TV Settings > Playback. From top to bottom, select "Deinterlace playback > Algorithm type "Bob (2x framerate)". "Preferred MPEG2 Decoder" "Standard XvMC".
Remove the check from "Enable OpenGL" and "Enable Realtime Priority Threads" and "Use video as timebase".
After this,I switched to "Watch TV" and there was my OTA broadcast of FOX 43 "Seinfeld" and I watched uninterupted the entire show. Next I was off to check some previously recorded material. I selected "King of the Hill" from the choices. Started playback, and watched the entire episode even skipping through the commercials, flawlessly.

I hope this helps someone, I know that every fix I applied I found in these forums. Thanks for the help!!!