i dropped my car off at the dealer this morning to get some other stuff fixed. i mentioned to them that my driver side dash speaker was intermittently not working. they just got back to me and said that the speaker needs to be replaced. so i gave them an okay to do the work. we will see if this will fix the problem.

your car must have a different radio from mine. i have a 94 E420 and my radio has two +/- buttons as a fader control. when i first encountered this problem, someone from this group mentioned that he too had the same problem and that changing the speaker fixed the problem. so i will wait and see if that does the trick on mine as well.

i picked up the car today. had the dealer fix the speaker. they ended up replacing it and so far, it's working fine. we will see if the problem is gone for good. the total cost of parts&labor was just below 100 dollars.