My Macbook Pro has been having some odd problems with the DVD writer for a few weeks now. I use Toast primarily for recording DVD-R and CD-R. Although the machine would read any media quite happily, I was having increasing problems with writing to CD-R and DVD-R. Out of a cake of 100 CD-R, I'd perhaps get a successful write with about 60, gradually decreasing over time to 20 or so. Not good. Googling suggested a dead drive.

Toast would give an error of "Sense Key=Medium Error 0x73, 0x03". Trying to record the disc from Finder would give me an error of "The device failed to calibrate the laser power for this media".

For reference, this is the device information:

MATSHITA DVD-R UJ-857E:

Firmware Revision: ZA0E
Interconnect: ATAPI
Burn Support: Yes (Apple Shipping Drive)
Cache: 2048 KB
Reads DVD: Yes
CD-Write: -R, -RW
DVD-Write: -R, -R DL, -RW, +R, +R DL, +RW
Write Strategies: CD-TAO, CD-SAO, DVD-DAO
Media: Insert media and refresh to show available burn speeds

What concerned me was after the drive failed to write to a disc, the cache line would change to:

Cache: 0kb

After trying the various fixes listed on forums (including Apple's support site) I only had one solution left - a lens cleaner. I've always been somewhat dubious about these things as they seem a little bit snake oil to me. Colour me surprised that it seems to have fixed it.