I looks as though you may be using poor-quality settings to export your video. What dimensions and settings are you using? I would recommend exporting your videos at dimensions close to that of your source videos using the "Movie to QuickTime Movie" option to begin with. Then - bring up the options dialog (to the right of the "Movie to QuickTime Movie" option), and: Make sure that in the "Settings..." window you have decent (i.e. high-ish quality) settings like: - Compression Type: H.264 - Frame Rate: either 25 or 29.97 depending on your videos - Key Frames: every 25-30 will be fine if you want to play the video in MixEmergency, otherwise select Automatic - Quality: High or Best - Encoding: (to test I would just leave this on Single-pass) - Data Rate: Automatic Make sure that in the "Size..." window you have: - Dimensions: Current Let me know if this fixes your problems.