Arduino Micro power not stable VIN

Hi,
Is there anyone that has measured the powerusage on the Arduino Micro while powering it externally by a 9vDC battrery on VIN pin?

With noting connected an just an empty sketch uploaded. for me the power toggles between ˜34mA to 330mA each 2-3 seconds? Is this the result of the onboard powerregulator?

However, compared to my UNO board has very stable power consumption powered the same way.

Thanks
Dibron