can anyone give me some insight as to how a video from pen drive that is in sync {video and audio match} can unsync when copied to my friends mac ? I don't see how that's possible .

What player is being used on each platform? What type of container is the file in? What codecs are in use? What decoders are being used at the time of playback on each machine? Those are all things that can contribute to this type of behavior.

the file is mp4 , and it played on the ps3 perfect , I copied to my usb stick , checked the playback of the copy on the ps3 , it played back perfect , copied it to my friends mac and the playback on his mac was out of sync , I don't know what player he used on his mac, I think he's giving me BS to get out of putting it on dvd for me

Tell him to get Perian, that will allow you to play a bunch of stuff from within Quicktime, and if he's going to be putting it on dvd with iDVD or iMovie this will help for that I think.

thanks , very interesting