I thought others here may find this interesting. We sometimes test with the top cover off our aircraft - we noticed some strange baro spikes in some test data. Long story short we were getting sunlight reflection off a piece of metal on our aircraft right into our MS5611 baro sensor. Turns out the baro sensos is sensitive to light so be sure to keep it in the dark!
The spikes below are when i turned the aircraft so the sun reflected right up onto the baro:
good to know. I’m sure you are suggesting open cell foam as to not seal off the pressure ports. I’ve usually got my autopilot mounted in a dark cavity inside the aircraft so I don’t see this issue ever in flight.