I had this problem with my Jeep Grand Cherokee SRT8. I called Valentine and followed their instructions to solve the problem. THe result was getting pulled over three times within two weeks because the sensitivity was reduced so much.
Needless to say I ordered my M5 without the "Driver Assistance Package" so I have no issues with false readings and everything works perfectly.
Can't stand that lane departure crap anyway. That's what eyes and mirrors are for.