Alt-Hold problem

I am using the Crius AIO pro board and running mpng's port of APM on it. It has worked flawlessly before but after a major crash and some modifications to the platform regarding changes in props, weight, reflashing, migrating from 3S to 4S battery and so on I don't know if the crash is the problem. Maybe it is just in the settings?

The copter flies super nice in stabilize and ACRO but when I engage Alt-Hold it goes nuts. So far I've only tried it for a couple of seconds before I feel like I have to go back to stabilize. The copter switches throttle at what seems random, falling at points and others climbing.

The baro seems unharmed and I've covered it nicely with foam not letting any light in and still giving it room to breath.

Here are some logs that I don't really understand. Looking at DroidPlanner while flying the altitude seemed to fluctuate a lot and at points reaching below -10 and above 20 when I'm only been hovering above ground. Testing the baro in the apartment and lifting the platform from floor to roof it seems go give nice readings between 0m and 2.2 (as high as I can lift).

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  • T3
    Did you check your vibrations. Altitude hold relys on accelerometer and z axis. Check the wiki for instructions on vibration.
    • thank you for your reply Richard. I will check it out. The background is that is has worked flawlessly in alt-hold before but they are lots of mods done and the crash combined. The stabilize mode is running really smooth so I just guessed the vibrations where low. I also have vibration damping on the FC to reduce vibrations but will check logs.

  • The Baro must be fried. I got for some reason signal loss with my transmitter today while flying and the copter entered RTL going crazy up and down finally almost crashing brutally onto the ground. Fortunatelly I got control again with the remote and could give it some gas to slow it down on its way to the ground. I'm declaring my baro on this Flight Controller dead. Won't use it again. Too bad =/

    If you have any suggestions please let me know and I'll try it out.

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