I've never used the frozen tracks feature, that I know of, but that thought had crossed my mind. Maybe I tripped it somehow. I will try to duplicate it with some of the ideas everyone has thrown out.

Mac- you may have hit it with Forte. Seems to me that I switched back and forth between VSC and Forte a few times before it happened. Low resources perhaps.

I mainly wanted Forte to do a higher quality rendering but with those kind of problems, I may just export to midi and pull it into Cubase to render to audio. The drivers in Cubase/Halion are sound pretty good.

My laptop is not the most powerful but the price was right ($0). A friend had it, said it wasn't working and for the price of a new hard drive, I got an almost free laptop.

Thanks to everyone for the great tips. I will check latency and also read through Manning1's post. Looks like that may take me a while. :-)

Ric