Have you used any firmware editing program such as MediaCodeSpeedEdit (though, from memory, that only changes DVD speeds, not CDs)? As LUK says, I can't believe those discs have those write speeds (and your first log in post 3 showed them as only 4x). With those high speeds, they actually look more like CD-Rs. If so, I wonder if they are being misreported as RW discs to begin with.
Also, have you tried to erase the disc in any other burning program? EG Ner0.
Finally, delete the PXHelp20 filter. It's unnecessary.
Regards