i don't know if it helps to post this late, however i have had the same problem with my m6809. at first i thought the burner was fucked, but recently i have tried the following with no good results :
used a new laptop burner
upgrade the bios for both computer and burner
used a 3rd burner that i know works from another laptop in my m6809. however, it will not work in my computer.
reinstalled a fresh copy of windows just to test it.
did all that usual dma enabling stuff and whatnot.
changed the bios drive settings a bit, both auto and manual settings fail.
what i mean by "not work" is using high quality verbatim dvdr+ media (usable up to 8x), it refuses to burn. i have used the same media on the other laptop with a burner and it works. despite advertised burning speeds, on my computer only 2.4x is recognized, and then it asserts my media as not capable of burning at that particular speed?
also, while my original burner was able to read dvds at first, within 3 months it couldnt (i didnt use it much), and can barely read cds. the second burner i used also had this problem. i fear my m6809 somehow destroys these burners. i'm horribly confused, and this ruins the portability of my laptop if i must use an external burner.
can someone please tell me what the hell is going on with it?