hi all i have a acer laptop with a MATSHITA DVD-RAM UJ-811 drive on it

i have burnt a few dvd's of various brands usind dvd shrink and easy cd creator

the problem i am having is playing them

they play on my old dvd player with is a chipped sharp 600h but jump about half way through

on my new player which is a panasonis dvd xv 10 (also chipped) which says it wll play dvd+/-r&rw's it wont even play them
could this be a drive player or a media problem

any advice welcome