I have recently encountered a navigation issue. The plane won't keep its heading between waypoints, but weaving all around the sky chasing for them. Mission still completes but in that weird manner. It was navigating perfectly before, the only thing changed in params is a turned off STALL PREVENTION. Just in case, I have replaced the GPS/COMPASS unit, can't test due to bad weather. Can't find anything weird in logs, so attaching one of a takeoff-landing mission, maybe you can spot the issue.
Wondering if I should start tuning the NAVL1_period, but this issue just came out of nowhere.