i find that very odd due to the way the drive is constructed, and the way the gears inside it work. when the tray is open, the lazer assembly should be lowered out of the way, and as it closes the lazer is lifted to the disk.....so what you are telling me baffels me, just in the design. check the white gears, make sure all is good.
as far as a fix, I dont really know what to say. its not good to run the 360 open, as the wind tunnel cannot properly cool the system, and COULD lead to a RROD. maybe think about externally mounting the disk drive??