I'm running an Asus MyCinema U3100mini ATSC on Windows 7 64-bit. When I play live TV in Windows Media Center, it's very choppy and uses 500+ MB of RAM, I'm guessing due to the hard drive buffering functionality. Is there any way to disable the live TV pause buffer completely? If not, can anyone recommend alternative software that:

1. Works with the MyCinema.
2. Is lightweight and not horribly bloated with features I'll never use like Windows Media Center is.

Edits:

1. This is a dual boot system. I've discovered that the tuner actually works fine on XP. It also works fine on my other computer, which has slower hardware and also runs Windows 7 64-bit.
2. The problem actually seems to be with playback at large screen sizes, not with hard drive buffering. Everything works fine below a certain window size and fails for large windows or full screens. Also, the same thing seems to happen whether playing live or recorded TV.
3. As far as the obvious stuff goes, I have the latest video drivers from ATI for my Radeon x1050.