Please help: ATI 650 video auido stuttering

[ChuckIT]

whenever i start up the CMC (cytalist media center)
and click on TV
my the tv starts up
i can use my comcast digital box to surf channels
but after like 5 minutes of watching tv the video STUTTERS big time, then the audio drops off and then it's just video stutter

I have windows XP pro, Fresh install.
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i've tried new drivers
i've tried disabling SLi in bios and in OS
i've tried hooking the cable directly to the tuner
(by passing the digital cable box)
still getting stutter
i've tried a different PCI slot, still stutter

i have not tried removing the second gpu card
(i feel this is not nessciary because my power supply is quite a beast, imo)

PC POWER AND COOLING SILENCER 750 watts (83 % eff)

im thinking the heat from these GPUs is causing an issue

have a TJ-09 Silverstone 5 x 120 mm fans

im thinking maybe there is a HEAT problem?
I am not ocing my CPU,MEM or aNY bus's (pci or pci-e)

[mewing8]

I have the same problem, does anyone have an answer. I called ATI- of course, no help.