Hmm, hard to say exactly without more info. What file type is the video you're editing - is it HD or AVCHD? What kind of graphics card do you have? That may play apart. Ultimately though, this sounds like something you'd have to contact Magix technical support over, to try to figure out what the deal is.


You can contact them through their website:

http://support.magix.net/magix_relaunch/php/page.php?lang=us