My clips are MPEG-4 AVC. My new camera is a Cannon Vixia HF 11.
My computer has the new Quad Processor, 8gb ram, using Vista 64bit.
I just downloaded and installed the new patch and my system says that it's now updated to the new 2227c.
I just tried again using a single clip and the patch seems to have eliminated the problem, at least with a single clip. I will now have to see how it performs with more going on (effects, PIP, music) and see if it still flows smoothly.
Thanks!