this is an open post for those who have issues playing home made dvds. I mean FINALIZED. My combo unit uses MINUS discs ONLY. 2 of my 3 towers played them well. The two towers displayed the "PLAYER MENU" showing the 4 players installed. The third did NOT detect the home made disc but DID play commercial dvds. I have no idea why. Since I am not very good at diagnosis, I decided to start over. I reloaded a fresh copy of XP. I then loaded the one and only codec that works with PLAYER 9 from COLE2K.net. Then I tested the installed dvd rom drive. NO GO still. I then tested every one of my rom drives and burners. Out of the 12 I have, the LAST one, a burner, was the only one that worked. Why I have no clue. I can only presume that MINUS discs are not commom. PLUS discs mut be. I think that the drives are made for PLUS or BOTH. This is NOT labled on the drive. That would be too easy. I know of no way to determine in advance if a given drive will work with these dvds.