Hey mate, the same thing happened to me sometime ago. I got the problem solved by ejecting the disc for a minimum 30 minutes before replacing it. Good luck, and you may have to do it more than one time.

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-2006 E53 (X5 4.4) Titanium Silver, fully optioned (sports package, premium package, navigation, ride height adjustment, panorama moon roof, rear climate package). Aero kit installed plus set of staggered 20s with Diamaris tyres.