I'm using the Power Mic Pro but may be having issues with the camera draining the car battery. The day after it was fitted (to a 3 month-old BMW X3) the auto stop/start didn't cut in at junctions. It was suggested this could be low battery so on Saturday, we did a 100 miles round trip and it works fine. The car has been parked since then (parking motion sensors turned off so no recordings) but this morning on starting we got a warning of an electrical issue. The car started and ran OK and we didn't get the warning again when starting to come home. This may of course be a general electrical issue for my BMW dealer to sort out but it's strange it started immediately after the camera was fitted - by an engineer from the company I purchased from.