Alt hold problem

when i put ALT HOLD during a flight , my Quad do a rotation of approximately 25-30 degrees then, after 5 minutes, he does it again, constantly.
Do you know if it’s a parameter to change or something else ?
ps:I use pixhawk 2 as FC

I assume you are using Copter 3.4. You need to share a log otherwise it is hard to help.

i will try to do a log tomorrow but the weather doesn’t help

Hello, here is logs, this time in alt hold , the quad has turned once alone, at approximately 35 seconds of the end (the date is incorrect) 2 01-01-2000 01-06-02.bin (3.2 MB)
thank you for the help

I’ve just realized that he do the same thing in stabilize

I’d change the title of the thread to reflect a yaw control issue, not ALT HOLD.

I see in the log that you get uncommanded yaw events. I do not know why. I also see that your vibration levels are high.

It looks like the desired yaw and estimate are reset multiple times by 15 to 40 degrees, but the yaw gyro shows no rate.

sorry for this late answer,
i’ve checked others logs and the yaw gyro never show rates, (i don’t know if it’s normal), i’ve recalibrated compass of the FC and apparently the problem is resolved but i’m not sure, i will do few flights before confirm it.