Hi, Ive been having problems playing .avi and mp4 files. I try to open them in Quicktime, Realplayer and VLC. Every time the program closes unexpectedly after a few seconds without playing anything. VLC does the best by at least playing some sound for 5-10 seconds before closing. These files used to work fine only a matter of a week ago. I tried re-installing all 3 programs but with no luck, I tried re-installing codecs like perion, divx and xvid with no success. The only files that continue to play fine are mpg, flv and wmv. I have no idea whats going on. please help!!!