There have also been a few instances I have seen over the years of people having issues with their amps and headphones in high humidity regions.
One in particular was a BHSE that stopped functioning and need to go back to Headamp for work... I believe it was 18+ months later that the individual that sent it in finally got his amp back, with a brand new main board and other internals due the corrosion that built up inside the amp. They basically had to rebuild the amp due to the damage from the humidity. see this area of the BHSE thread:
https://www.head-fi.org/threads/headamp-blue-hawaii-special-edition.439657/page-266#post-9816489
So yeah,
@nepherte, I think you are getting lucky, IMO, YMMV and all that....