I have just finished re-building my hexa and on the first flight noticed a very strange behavior (which caused a big crash already).
First, yaw drifts. It happens all the time, and in different directions and with different speed too. I suspect it's something with EM interference, but why does it spin different directions?
Second, hexa does not respond to transmitter immediately after 5-10 seconds of flying. It's just weird, I try to hover and give it a bit of left-right and forward-back movement, but in some time when I try to pitch forward, hexa goes sharp left, then back, then forward. Or right. It looks like it tries to compensate previous movements first before responding to sticks. It's hard to describe, I'll try to make a video tomorrow. Do you think it's PID controller overcompensating?
I'm using standard PIDs, the frame is HK 650x6 with NTM 28-36 700KV motors.