Hey,
I am running ArduCopter 3.0.1-rc2 on a Crius AOIP Flight Controller and i connected it to an NEO-7M GPS Module.
The flight controller recognizes the gps module and gets a fast gps-fix on the right coordinates. But then it constantly drifts of in one direction - even though the copter is not moving at all.
I checked the gps module in ucenter and it doesnt drift off there, the coordinates stay stable. I followed the instructions on this page to set up the gps configuration for the gps module with ucenter: http://ardupilot.org/copter/docs/common-ublox-gps.html
I also connected a neo 6m module to figure out if the gps module might be the problem - it showed the exact same behaviour.
So i guess the problem must be in the configuration of the flight controller. Any ideas what might be wrong?