Another V1 failure mode

My v1 has failed after about 300 shots.

Displays error message "! An error has occurred. Press the shutter button again."

Doing so results in a double shutter click like sound and the same error message.

Changing lenses, powering on/off, resetting shooting options, battery removal for a short while, etc. do not fix the problem.

It is warm (low 90s) and humid here at the moment.

Any ideas? Is there a higher level reset? On vacation without any other cameras.

Bob