Liteon ldw-401s (help...)

Hi I’m not new to burning but I an new with dvd burning (although it should be able the same) anyhow. I have a problem, I just got this drive and I think it may be deffective. It burns movies fine on the RW disc that came with the drie but when I try to burn +R discs it just sits there barely burning and blinking red the whole time it too 16 minutes to burn 686k with nero 6.28 (I cancelled it). I have killed 2 discs already the one that came with the drive and a sony +R disc (ricohjpn identifier) I just got, I don’t wanna waste more discs, is this a drive problem ahould I rma? I have the latest firmware installed, have burned many movie backups onto the dvdrw disc but nothing works with and +R discs

help please Idea’s helpful and much appreciated