Media/CD detection problem with LTR-52327S

A while ago I started experiencing CD detection problems with my LTR-52327S (firmware QS5A, but it happened with the previous version too, the QS58).

Some medias require many trys of ejecting and inserting before the drive shows that there is a media inside and can write on it. This happens also with these medias after the burning (burned with either this drive or a Plextor Premium). For other medias less tries are needed (like pressed CDs).
This happens also before windows loads, even if these written/blank CDs were inside the drive when the computer was turned off, and then I turn the computer on (to boot from the CD for example), the drive won’t see the CD. So it seems this is not related to a Windows issue.

The drive is connected as the primary-master to an Asus P4C800 Deluxe mobo (bios 1019), a Plextor Premium is connected as the secondary-master.

Is my drive malfunctioned?
Anything I can do about it other than just RMA it?


WinXP detects both drives to be working at DMA2.
Could this be a DMA problem (even though the drive is “supposedly” working in DMA2, as I’ve heard that there are sometimes bugs with mobos that shows drives to be working properly at their optimal DMA mode, but actually they aren’t)?

Strangly, the Plextor read CDs at a much lower speed than it’s capable of (52X).
The Liteon does reach its max speed though (but this could still be a difference between the primary and secondary IDE channels that is related to a possible DMA bug).

Upper capture is the Plextor, lower is the Liteon: