lots of info in that post im guessing its a + or - format compatability issue,but who knows from all the info
If you're saying that your standalone player plays the disc but your friends players won't, then it has to be a media issue. You have propably used some cheap bulk discs, they often have problems exactly like this. Well I hope you get it figured out, but as jim_dandy already said, please try to give us a little bit more info about your problem, i.e. what software you used, what media you used... that would be a good start and would make it much easier for us to help you out! Cheers!