I just got a GH3 and I'm using a Lumix 14-140 F3.5-5.6 zoom. As soon as I attach the lens and turn the camera on--even if the camera is in manual mode, with manual focus--if my ear is within, say, 3" of the camera (the side where the lens attaches), I hear a subtle but unmistakable noise that sounds a bit like a grinding motor but that you could also convince me is something electronic.

Does the GH3--or could my lens--have a motor that runs even when the camera is in manual mode (even for stills), set on manual focus, and is simply sitting there, pointed at a surface with a constant exposure?

I've got the OIS switch turn off on the lens, as well as every camera function I can think of.

The only time that the sound goes away is when the camera is in "Scene" mode--but as soon as a scene setting is "set," the noise comes back.

I have updated the camera to the 1.2 firmware.

I've never worked with a DSLR before, and I'm a bit of a newbie in general (most interested in video). Is this normal?

Any help appreciated!

Thanks!