AltHold Baro problems

So, I have to assume there's some code that takes this into account, but I have a problem with the Barometer. I have an SK450 with an APM 2.5+ with 3.0.1. When I'm in alt hold and the copter is not moving, I have no problem with holding altitude, but the instant I move side to side, the indicated altitude increases on the telemetry, while the actual copter drops in altitude. This happens in Loiter and AUTO as well.

I will try to find some logs for this, but I'm not sure they will help, due to the nature of the problem. I'm pretty sure this is due to the fact that if you move into the moving airflow from the motors, the pressure changes slightly, and the autopilot compensates by decreasing altitude. This continuously pushes the barometer into the moving airflow, continuing the problems. Any ideas for what I should do?

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  • Make sure your barometer is protected from wind and sunlight.  Normally, this is done by having a piece of foam or cotton over the barometer itself and some black tape or other light-blocker over the area containng the barometer.  I normally enclose the whole APM inside another container with only a few small holes for wiring as well. Performance is better if this is opaque black but then you can't see the LEDs on the APM.

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