Smart Car AC Issue

I have noticed if I have my AC on 3 every once in awhile, the speed of the AC fan will slow down and still blow cold air and then it goes back to the speed it was originally on. I had at first thought this was an economy feature on the Smart but when it happened the first time, the AC console shorted out and the AC would not turn on. It is starting to happen again. We have taken it back to Mercedes and they can not figure out what the issue is.

Does anyone else have a problem with the AC blower motor changing speeds when you have left it on 3 or 4?

Thanks!