So i've been trying to build a quad for a friend of mine. 

I currently have a DJI 500 style quad, Sunnysky 2212 980kV, 10x4.5 props, APM 2.6. That's about it.

Anyway, flies great. I have a pair of graupner 9x5's i used and they were solid in stab mode. The issue comes with Alt-Hold, as soon as i put it in the Alt-Hold mode, the drone pops up and down pretty fast. There's something wierd with the baro, i've tried two different APM boards (both 2.6), tried different variations of foam covering (from lots of foam touching baro,  little foam touching baro, box foam over baro not touching). I even thought it was crazy prop-wash so i covered the entire center bit in a trash bag and rubber bands.

I also have two miniAPM 2.6 boards that have the same issue (but that was on a 250 size, the vibrations were killer). Anyway.

So can someone take a look at my logs and see what i'm doing wrong? Is it two bad boards? or am I totally screwing some PID settings somewhere?

I've built drones on these boards before and they worked great, but that was a year or two back with 3.1 and 3.0 code (before drift came and was awesome). I also have a pixhawk on my camera rig 700mm X8, and it works great. 

So the only thing I can think of is code, they're on 3.2.1 or whatever the latest is today. The logs are of me trying to alt-hold this morning. I erased and reflashed the board today, so this should be as clean as i can get it. I start off in stabilize, it's a little twitchy with the stock settings so i lowered the settings a little.

I'm also attaching my PID settings just incase it's not in the log. 

Thanks in advance for any suggestions! 

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Z axis vibrations! I've had a look at your log, and they're really bad. They should be between -5 and -15. From this log they're between +20 and -30. 

Your X and Y vibrations aren't too good either. Have a look at balancing your props and giving the APM some damping of some kind. 

Get rid of your vibes, and you should be good. Some good reading here:

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