This happened to mine a few weeks ago, i put a CD in the stacker and the nav went crazy, going back to the old menu and not letting you select NAV. So i turned the car of for about 3 hours then, i unplugged the batt and when it turned it all back on it worked fine,


Hope it helps

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2007 E70 X5 3.0D Black/Beige - SOLD
2012 E70 X5 40D Silver/Black