Coasters with LG Burner - HELP !!

[gschilling]

For some reason, I am getting an unreadable disk with every other DVD I burn using my new LG 4040B burner. I've tried both CloneDVD and Burnatonce, and both give similar results. It always tells me that my burn is successful, but the disk is not recognized by either my Pioneer DVD-ROM or Toshiba DVD player. I am using Memorex 4x DVD+R media. I have a brand new P4 machine with 1gig of RAM and all the high end stuff. Any ideas why I could be having a problem like this?