My 2000 ML320 did great recently pulling a 4000lb. trailer from Atlanta to Littleton, CO. 1400 miles!

Ever since she (ML320) arrived in Denver shes been acting up. He are some specific symptoms encountered with the "stuck" buzzer/warning chime:

1) only happens on cold start up
2) turn the ignition off and back on and the buzzer unsticks
3) sounds as if buzzer/chime is below the instrument cluster
4) despite seat belt on, parking brake released and no other buzzer related faults, the buzzer/chime comes on and stays on unless ignition turned off and on.
5) I'm thinking the cold weather here is sticking a relay that drives buzzer/chime module.
6) took her to the Littleton, CO. benz dealer and they could not re-create the problem.
7) never happens on warm start up but about 85% of the time on cold start up despite her being in a garage and not in the sub zero outside stall.

Gilly, I have never addressed you before but sure have read alot of your advises. Good stuff, any ideas on this one?