I found my on/off button (2001 X5) sometimes sticks when depressed - result is similar to your complaint - I had gotten into to habit of pulling it up (gently) - "had" because I replaced the 4:3 nav display with a new 16:9 on Friday.

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Mark _______________________________
2001 X5 4.4i topaz blue/sand Sport, complete Dinan S2 , hitch, V1, tint, BSW Stage 1, Alpine INA-W910BT
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