I have 3 flat screen tvs connected by vga to a distributor box?

which connects to a computer running video images regarding my sales for the month. For some reason the video image keeps freezing instead of looping the playlist, but ONLY while connected to the TVs! When I tested the video files, they ran full screen for 2 days non-stop on my computer which has equal or less memory then the main comp. I'm using media player classic to run a loop of custom commercials that were originally mpeg, but now mixed down to .wmv in an effort to correct the problem. Any thoughts???