I noticed the other day in the car that my screen was no loneger locked into landscape the way I like it. I picked it up, it rotated it and the switch was engaged.....so I flipped it to unlock, then flipped it back again and the audio 'sound' icon came up, not the lock indicator....happens all the time now...the screen will not lock and that icon comes up when I toggle the switch. has anyone has this issue before? heard of it etc.?