Depending upon when it was made many brands had problems with software compatibility with the DVD's. It could also be a weak laser causing the picture to freeze when the DVD switches to the next layer.
russ, June 2004
I don't know if you have tried this, but it could be your dvd player needs to be cleaned. I had the same problem and bought a scotch laser lens cleaning disk for about £6 and worked fine after. Hope this helps?
Andrew Spencer, May 2004
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I can answer this question...
dvd player pauses dvd in middle of scene- how do i fix this problem?