Doug was showing the Task Scheduler. Heres a
link to his attachment to view it full size.
Ahh, that's right. Couldn't tell from the severely resized screenshot.
get a new PC that will handle this stuff better
Uhhh... it's not like I'm running a Commodore 64 here.

AMD Dual-Core 3 GHz CPU, 2GB RAM, 3.5 terabytes of hard drive, nVidia 8600 GTS video card with 256 MB...
Ah yes, then you're right, that should be more than enough computer for what you're trying to do.
One thing that did work beyond my expectations was increasing the priority. As an experiment, I set the priority to "Realtime" and ran 44% more simultaneous audio streams than I had ever successfully run before...
Cool, I'm glad it worked then! Chances are, you'd probably be fine with High or just Above Normal, though.