I got an 05 uplander a couple months ago and haven't messed with dvd player much but with a beach trip and a 6 year old any advice would be appreciated.

The dvd plays dvds sometimes. One in every nine or ten or so. I've tried some discs multiple times and if they play it plays them each time and if they don't it doesn't. There doesn't seem to be any rhyme or reason to which it decides to play. The few it will play are course not his favorite movies. Does anybody have any ideas on why or how to get it to play more? You're a daisy if you do.