This sound pretty much what mine is doing now, but maybe only beep for 20 seconds. At least it does stop. It's not the big of a deal except when you want to throw something in the passenger seat, which I do all the time.

 

I havent tried this again yet, but I'm going to tonight.... I remember I had some problems getting it to work he first time... I ended up getting my girlfriend to sit in the passenger seat to buckle the seat belt while I held the odo button.... Maybe that had something to do with it. In any case, all I can say is I know for sure it can be done on an 08 tC using the steps provided, or some slight variation. I tried doing it from memory just now and I ended up holding the odo while holding the brake turning the car on, I noticed it did some type of count down... who knows. I'll look into it on my break coming up.

 

After searching some more, I think I've found a shorter version... maybe it'll work better.

turn ign. to on position
switch to odo view press and hold for 10 secs
while still holding, buckle drivers belt
hit odo button to toggle b-on or b-off

 

So have any xD owners gotten this to work diy yet?