Here's an odd thing that happens in my office. I haven't noticed it happening in the field.
when powered up, the servos constantly jitter
jittering seems to be going through the APM... note the period of time when APM is booting and jittering stops
jittering associated with 900MHz xbee
if the xbee is disconnected, no jittering
if I ground the xbee by touching the antenna, jittering stops
I'm curious as to the cause of this; partly to see if there's a problem, fix, etc, but mostly to understand what's going on. The primary practical issue is that the jittering noise seemed to make people nervous as they were looking at the unit.