I have+know at least four Solo's with this issue.
OpenSolo 3.0.0 , ArduCopter 3.5.7.
The problem;
The camera pitches up, at 3second interval, with logarithmic steps.
It does so if the last input was a slight "up" (look up) command, not if the last was down.
- not sure if it's related, but the...