thanks for the reply

well im using MSP 6.5 and 1.33 GHZ with 512mb ram... so no issues there

this problem only really occurs when the titles are displayed... there white with text and a watermark type background.

I export using a stand alon HDD also.

The titles are only for the first 15-20 secs and after that its fine...

could it be something to do with the titles? like colours i have used?