Is anyone else having a problem burning DVDs using the TS-H552L DVD burner. Most of the time lately it seems to stall out while burning. It does eventually finish but the burned surface of the disk has dark rings. Most of the time the backed up movies play fine but I have wasted quite a few blanks with this problem. Also I've been using the same blanks for over a year now so unless this is just a bad batch I'm pretty sure it's not the Sony brands DVDs.