Well your in luck, first of all its a Benq drive, so there for its one of the easiest to flash, I have had this promblem my self, and its probable a mobo issue, which is no big deal,
SO step 1- is to get another benq drive being that there are the easies to replace.
Step 2- you dont need no fancy tools to flash a benq drive, so theres another plus you can do it right from the xbox 360 just need alonger sata cable.
Step 3 is to get the key off it, which i persnally can help you step by step on here or on yahoo which ever is easier,
Step 4 when ever your ready to start the process PM me and we will get this fixed asap
will give you step by step instructions to help you along