Great guess ... I'll check tonight. It has a Sony radio with a detachable face. Hard to tell where it is comming from. It could be a "stero" beep. The car is new to me and I am in the process of "debugging" all of the little stuff that is totally correct.
190SL, 230SL 5-speed, 95 E320 Wagon, 01 E320 Wagon, MGB, Boxster 'S', 190SL "Barn Find"