My D300 makes kind of an electronic "whistle" when thecircuitry does it's thing. Can anyone else hear their D300 whistle when it cleans? It's like a rapidly descending whistle. My D700 does not behave the same way, mind you I've had it since new and the D300 is used - tho only very little from what I can tell.
EDIT: Apparently it IS normal to hear it, though it should be fairly faint. As a tinnitus sufferer I'm humbled to know I can still hear subtle noises... tho at the same time now that I've heard this sensor clean tech once I'll hear it e-v-e-r-y single time! If anyone else has anything to add about the , feel free.