This issue occurs with both DVD-R and DVD+R. I put a blank DVD disc in. It takes a couple of minutes to read and then it says that it is preparing the disc. It starts at 25% and ejects the disc when it gets to about 27 or 28%.I have been using DVD-R for a while because I could get it to work most of the time after trying several times. I had started getting invalid disc messages for the DVD+R discs a while ago and stopped using them. They were Verbatims. I have tried a number of brands with the DVD-Rs. I was using Staples Discs for quite a while as they were working fine. Another issue I have been having with the Presidian PDR-3222 is the disc door does not open when I push the button or use the remote. I have to manually assist it and this is getting harder to do too. It has no problem opening when it is rejecting a DVD.

Televison & Video - Dual - Presidian DVD Recorder