Default [Q] USB Mass Storage Problem

Hi all,

I want to use my Desire C (CM10) in my car only for navigation using TomTom and to play Music via Kenwood Music Control app.

To use it with my Kenwood Car Audio System it has to be in USB storage mode. All the TomTom stuff is on sdcard aswell. In MSC the sdcard gets unmounted and therefore force TomTom to close without access to the map data, right?

I dont know how to handle this problem. Any ideas?

Best regards