Quad wander off in loiter mode

[attachment=0]APM at Jordon 13 May 2015 (2).log[/attachment]Quad has APM 2.6 clone from Good Luck Buy running ArduCopter 3.2.1. It flies OK in stabilize mode but when I switch to loiter it drifts away, typically moving 75 meters in 3 minutes. This is with 10 satellites and HDOP 1.62 meters. Accelerometer and compass are calibrated and working correctly. I have previously used Crius AIO Pro flight controllers on a couple of quads and these loitered very precisely so I was rather taken aback with this behaviour. I would appreciate some help or advice. Attached is a log file.

Found out that the problem was due to a transmitter issue and nothing to do with the GPS.

Hi Dorset,

I have the same problem. Which was your Tx problem. Can I send you my log file?

Sincerely,
Georges

I am having the same issue, Quad is perfectly stable in Stabilize and Alt-Hold mode but starts wandering away as soon as I enable loiter mode. have tried everything, GPS and compass calibration are all spot on.