yes, roll servo does it in nav mode too. there are times were it doesnt wonder as far away from the set hdg though, but its never held dead on, YET. i'll re-calibrate my remote compass to b sure. the pitch servo should be ok. mike had me send it in to be checked(rma 8607). i just got that one back from yall. BUT, after i sent it in, i didnt want to wait, so i ordered another one from a/c spruce so i could get it in and back in the air. if you like, i'll swap it with the servo i just got back from yall and try it?? hard to believe 2 different servos would be bad though?? one more thing i noticed. while in altitude hold at 5500' last weekend. the a/c would go down around 5000' then back to 5500', then up around 6000', then back to 5500'??