DVD-R Playback Problem

Please if anyone can help. I am using AvidXpress DV 3.0 to edit, sending it to Sonic DVDitPE where I set up Menus for the DVD and it converts the sound to Digital. Avid converts the video to MPEG-2. My problem is (and this happens on various machines from different companies) that I can play the disc i created on a DVD player and it will play perfectly and then when i play it again it will pixilate or freeze. Then on another attempt will play perfectly. Can someone tell me why this is happening and what I can correct it in the future? By the way I am supposedly using TDK DVD-R discs. Thanks for any input.