That's odd - I'm not even sure how that could happen, unless perhaps you've somehow managed to MIDI map your crossfader to media bank.... You can see in MixEmergency that a new media/video is being being loaded each time you move the crossfader across (as the Random transition keeps changing - which it only does when a new piece of media is loaded). Can you e-mail me your MIDI mapping file so that I can have a look at it? You can find it in ~/Movies/MixEmergency/Control Mappings/_AUTOSAVE.xml