My DVDwriter does not recognize bootable disks

hi,
i use windows xp and ubuntu linux dual booting. i have a sony DW-Q120A. the problem is strange.

i am able to write cds, dvds, can read cds, dvds which i have written using this writer, can read movie dvds and most of the type of cds.

but the device does not recognize bootable cds and dvds. for example, i got a dvd from a magazine which can boot to install linux and contain many windows programs as well. the drive does not recognize this dvd. i have put the dvd in many of my friends computers, it works just fine…both at time of booting as well as in windows. later i found that this drive does not recognize any bootable disks at all. i mean, the drive does not recogize any bootable cds or dvds either at time of booting or while windows or linux is loaded. after trying to read it for some time, it tells that “please insert a disk into drive I:” thats all…i have tried updating the firmware, cleaned the lens with clean paper etc. but of no use…

can anybody help me in this…???