problem with background video clips in MediaLab2010 and Windows 7

Hi,
I have problems with a questionnaire that involves scale responses for video clips in MediaLab2010 on Windows 7. The video clips are WMV files shown as BackVideos. Each time a response is given before a clip has actually ended the next video appears either on the lefthand side or in the top left corner of the screen, together with a blank,black square at the location where the video should actually have been shown. This problem does not occur when the response is given after the video has ended. Also, the problem does not occur in Vista.

Can you tell me exactly what version of MediaLab you have (i.e.,v20xx.x.x) and what version of theWindows Media Player you have on this machine? Also—is the small black boxexceptionally tiny? If so, could you possibly attach the .que file you areusing?