I've been troubleshooting Altitude loss in primarily forward flight. Left or Right roll into a wind results in the same altitude loss as well as being more pronounced when flying into the wind in forward flight. Backwards flight seems to not suffer altitude loss or not to the same degree.
I loose about 10-15 feet of altitude when this happens. It recovers the altitude when I release the sticks and resume hoover
The only other symptom I've noticed a small yaw when transitioning to forward flight which I believe to be unrelated.
My configuration is a DYS D800-X8 on Xrotor 40a spinning 4114 400kv 15*5.5 props. Running Pixhawk 3.2.1
So Far I've:
1) Turned EKF Off. - No Change
2) Tried a Softer Foam Mounting scheme. - No Change
2) Increased AV_TC_Z to 7 - No Change
3) Moved Pixhawk from top plate to a lower plate below the frame - No Change.
when I look at the logs I see the barometer indicating an altitude loss while the ctun alt remains relatively constant. But I could be reading the logs completely wrong.
I'm certainly running out of ideas on my end. I'm willing to donate / pay for help. My other option is to go to the Tarot FC or worse a DJI WKM or A2.