I have a Marantz DV7000 DVD player which is a bit tempremental but plays 99% of discs 99% of the time! Some time ago I brought the region 1 version of The Guns Of Navarone but have never watched it. It must now be about 18 months old. Sunday afternoon I decided to watch it and was supprised to find the film very blocky in parts. I tried the disc in my mates Tosh 2109 and no problems whatsoever. However, trying the disc in my player again showed signs of blocking. This appears to be the only disc that has a problem, though a little while ago, I had a similar problem with the R1 versions of The Negotiator & The Mask Of Zorro. A little shifting of the equipment on the racking soon sorted that. I had my Denon 3801 underneath the DVD player and heat rise as they say! After moving the kit, no problems. Until now. And only on the one disc. The place where I brought it have offered to exchange it if it shows faulty on their player, but I fear after todays experiment, it will play o.k. (service above and beyond the call of duty I'd say after 18 months!!) Any Suggestions Fellas?! I suspect Laser aligment.