Hello,
I have been having this same problem. This has happened to me on the past three trips from Spain to England with three different map DVD's and on two seperate OS versions. The system will work find for awhile and then the whole system will lock up on me. I can not use the Nav screen for anything. After awhile (varies from maybe 25 miles to maybe over 150 miles) the system will kick back in again. I also noticed a couple times if we turned the car off for a break that when we returned the system will work again. I am thinking of buying a protable Navigation system to replace this one (which is a shame and waste of money) as I am very syspect about the built-in Nav system in the X5 and it is driving me round the bend . I have tried to clean the DVD's and the system itself with not much effect. Anyone have a clue as to why this is happening, and what I can do to solve this problem? Thanks