I have a problem with altitude during auto missions. The system takes off to the correct altitude and then during the missions slowly descends and then ascends towards the end of the mission. really strange. The sonar is a bit noisy but kicks out the correct ground height most of the time. It's a 10m sonar so my flight heights mean that the system should be using this over the barometer. Tlog attached.
Pic as an example - desired vs actual
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