hi, last week i tried burning a dvd using roxio toast, but before it began to burn it says the following error: the drive reported an error: sense key = medium error sence code = 0x73, 0x03 i tried to use another dvd, but it is saying the same error (i have been using the same brand of dvd before but never encountered such problems), so tried to restart, and it proceeded to burn, no more errors, so i thought it was only a one time thing, so today, i tried burning again, the same thing happen, the same error, i tried 4 dvd's but the same error keeps on happening, but when i restart the macbook pro, it would proceed to burn with no errors. i wonder what seems to be the problem? my dvd drive or the software? anyone encountered the same problem before? i hope somebody can help me.?