I purchased a pack of 100 Memorex 4X professional DVD-R discs from UK, but they've proved to be a source of frustration. Pioneer DVR-105 doesn't recognise the disc properly, the disc keeps spinning like mad but doesn't show up in any media info utility. Toshiba 6112 kicks out the disc right after insertion. Nec 1300 reads the disc (Media ID shows SMC as manufacturer), but doesn't even begin the burn process. What the heck is going on?? I've tried all kinds of no-name brands, but never have I encountered a batch of discs that all seem to be totally unreadable! I ordered these from overseas and sending them back means an extra cost as well. I contacted Memorex, but have had no response yet. Has anyone heard about this? Are there batches of Memorex 4X going round that are this fooked up? I know for a fact that loads of people are using these discs with their DVR-105 with no problems.