Thanks for sharing! It could be a good tip!
Excuse approximative English..
But in my case, with MM15, I keep having problems mainly with the video when I am adding visual effects, then my PC which I just bought (HP pavilion dual core DV7 intel P7350 2Ghz graphic card ATI mobility Radeon HD 4350) jumps in and out.. My graphics & music are not fluid.. :(
I have all the time to mix my down