Thanks for the replies but nothing seems to solve the problem.

I drove 800 miles in 12 hours yesterday.....Phoenix, AZ to Elko, NV..... I had the top up for 450 miles and heard the chime maybe 5 or 6 times. I put the top down in the late PM when I got into cooler weather and drove until midnight with it down and heard the chime another 5 or 6 times.

I thought for a while that it was associated with cruise control but I have heard it when driving in town or otherwise not in cruise control. As others have said, it happens so rarely and so quickly that it is impossible to catch an associated warning light but I don't think there is one.

Keep the ideas coming, guys.

P.S. I brought my Xfire to NV in preparation for the big rally in Reno in August. Anybody on this thread going?