Motor speed hunting while hovering

Hello everybody,

I have been working on a QAV250 frame with a pixracer flightcontroller. The ESC’s are Blheli_s 30A and the motors 2205. Since the beginning I have some problems with a hunting or jittering motorspeed on all motors when it takes off.
When it is armed and slowly spinning the rpm is nice and steady, but as soon as I turn op the throttle the speed isn’t stable.
It seems to me it is reacting to something, but I can’t figure out what. Because of this the y acceleration is also quite high and noisy.
To test I’ve switched flight controller to a beta flight F3 acro (I’m not sure what kind of hardware it really is). In this setup the rpm is nice and steady, so I figure it can’t be the ESC and motors.
The vibration dampers on the pixhawk are also exchanged, as a test, but with no result. I tested foam and a 4 direction rubber damper.
I am a bit stuck in what else to try, because the PID settings it doesn’t seem to respond to (at least, with no improvement).

Is there anybody who recognizes this problem and knows how to solve this? Hopefully this is just a dump newby setting so I can fly normally afterwards.

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Post a link to a .bin file flight log. I have a Pixracer on a 210 frame and it flies great. What size props and what battery power (3S, 4S?).

I’m using 5" props with 4s batteries.
The log file is too big to upload here, so this is the download link:

It doesn’t look like you have followed the Initial Tuning guidelines. A small quad will not fly on the default filters parameters with Arducopter.

Connect to Mission Planner, start the tuning plug-in by hitting Alt>A, enter the information as requested then manually make the changes suggested. You should probably set the PID’s back to default. Your attempt at changing these is futile w/o making the basic tuning changes 1st.

Then you should configure the Dynamic Notch Filter and after that run Autotune. But setting the tuning parameters should get it flying.

Also, not sure what’s going on with your battery but it looks like you killed it.

Thanks for the advise. Somehow I missed totally the initial tuning guide lines and it makes sense that the drone won’t fly this way. I’ll update here after I tested it.