i don't know whether the temperature is the cause of this problem. it is in the low teens overnight. in the morning, i started the car and the radio gets this really weird loud static sound with really low music coming from all the speakers (i changed to different stations and they all sounded the same). i turned the radio off but the music and the static sound were still ON. i removed the key (that usually shut down the radio) but the music and the static sound were still ON. i locked the doors with the remote and i still could hear the music.

i waited a couple of minutes and were nervous now since i was afraid that this condition would drain my battery leaving me in the cold.

i opened the door and started the car again and everything went back to normal.

i shut everything down and took my trusty toyota to work fearing that the merc might leave the stranded at work if the radio started acting weird again.

came home, started the merc and everything seems normal so far

 

I believe that konigstiger posted a TSB in regards to that in one of his many stickies. Might read that and see if it helps.

 

Mention:

1) P-B-82.62/361a DEC04 Crackling & static noises from speakers when radio is on may be caused by bad grounding of the Audio Gateway (AGW).

2) P-B-82.60/382a MAY06 Will allow for COMAND head unit software & AGW software to be updated which will correct multiple malfunctions.

 

thank you.

 

Try removing and replacing the NAV DVD, it appears to reset the unit and it corrected a problem I was experiencing.