Plextor Premium burning issues!

System Configuration is:

Windows XP Home----- No Service Packs Installed
VIA KT400 chipset
Plextor Premium fw.106

i have recently been using BlindWrite and Discjuggler for backup purposes. I have realized that some backups being made cannot be read back in a Plextor 8/4/32a or MSI 52x cdrw. I have been testing on different media; fuji film, memorex, dynex, and imation with same results. I have noticed that any burn higher than 4x creates coasters. A coaster in this situation could be a successful burn; however, windows hangs while accessing the created cd. I use CD-Dvd Speed to run disc quality checks and come up with over 3,000 C2 errors. If anyone has a clue to what might be causing this please feel free to post; i am stumped!!! Nonetheless, i have flashed back to later FirmWare versions with no success.