video capture problems

Hello folks, I have the following problem:

I'm trying to transfer some 8mm and Hi8 tapes to my hard drive, and later to DVD. I guess I know a thing or two about computers in general, but I'm a real newbie as far as video capture/editing is concerned. The problem is like this:

For some strange reason, the AverMedia TV Tuner card doesn't "recognize" any of my sound cards (I have an on-board nVidia nForce Audio chip, and a Creative Live PCI card).
In the settings menu, on the Audio tab, the TV Tuner just says DIRECT SOUND, and the drop-down box is grayed out, so I can't choose anything.

When recording smth from the tuner, it works perfectly, but sure enough, as soon as I select S-Video from the Source Menu, the recording is mute.

I've tried NUMEROUS other video capture programs, and they recognize the sound card and give me sound, but the funny thing is that on EVERY SINGLE other program that I tried, I keep getting framerates like 4-5 fps in the recording. Which sucks.

Any ideas, folks? my system specs are in the signature, could it be because of insufficient resources?
If not, do you have any suggestions as for other capture programs?

Thank you very much in advance!!