2003 E500

It took me awhile to find a MB board and maybe you have some insight to this.
I bought a new E500 in October 02 and had multiple electrical problems including tele-aid system, lights, radio, and most disturbingly air-bag's only working intermittently.
They replaced the main computer once and some other parts several times. In May they finally just gave me a new car.
Well guess what, it was in shop for 10 days because it has same audio problem (I was told they keep getting too hot). They had to order new fix from Germany and my audio system lasted another week and a half but is out again. Car has 859 miles and has been in the shop for 12 days since I got the new one.
I am at the end of my rope. Is this a common occurrence or have you heard of any other major issues with the new E class?
This is my first post so if in the wrong section, please move.
Thanks