I experienced identical symptoms a few months ago (driver side only, clicking noise, on --> off). In addition to all that, the power controls on the driver side were very glitchy. In my case, it turned out the driver seat wiring harness was shot. Swap it out and you should be done. $72 for the harness, dealer wanted $900 for labor. I had it done at an indy shop for half as much.
"... but really, you just gotta ... you just gotta turn it all off, boys! You gotta turn it all off and you gotta wreck some tires! That's what M cars are all about, isn't it?"
-Chris Harris on the f80 M3