BMW Repair: 2000 X5 Crank/No Start, faulty chip, electrical portion

Question
I have a 2000 X5 (VIN=LH06109) with approx. 75K miles on it.  For the last few months I've had problems starting the car.  The starter will crank, but the engine will not turn over.  There seems to be no common thread to the problem... Sometimes it turns over first try and sometimes it will take 10-15 tries.  Doesn't seem to matter if engine is cold or is warm.

I've made 3 trips to the dealer to try to solve the problem.   One fix they tried that did not work was a software update, and the other fix that didn't work was a replacement of the unloader relay.

The car does not throw any fault codes, and once it starts there is nothing out of the ordinary.  Inspection II has already been performed and spark plugs were replaced within the last 10K miles

Answer
Mike, I don't get it. If the starter is turning over then the engine is most likely turning over. Unless the starter is not engaugeing the flexplate. What happens exactly when you turn the key to the cranking position? If nothing happens then mark your key and try a different master key and see if the problem continues. An intermittently faulty chip inside the key. Also try the replacing the electrical portion of the ignition switch if switching keys shows now result. I've seen many ignition switches do this.
-Evan