Samsung HR720 problem


I’ve got a Samsung DVD-HR720 and apart from this problem it’s a brilliant player. What happens is that whatever I record, and whether I record it to DVD or harddrive, the programs that are recorded periodically dip down in brightness then come back up again immediately. I’d say it happens every 2 minutes or so at random. As it’s not constantly changing brightness from dark to light, it can’t be a macrovision problem, and if it were a macrovision problem the recorder would just refuse to record, right? has anybody else got this problem? Samsung had never heard of the problem and advised me to send it straight back to the retailer, but I want to make sure that this won’t just happen again with a replacement drive (as its such a hassle getting the player back as its an online purchase)