when i download video files from limewire and bearshare some of the files will play but i can only hear the sound. the files that do this are .avi and i play them on windows media player. when i play them the file name on the side panel goes orange with a ! like it usually does if the file is corrupted. does this problem root from the downloaded file or is it something(ie software) that is or is not on my computer? i have been able to download some files successfully though. thanks!