Humidity causing bad shifts

[cybergomer]

The problem I've got is the trans basically dropping out of gear at will. Sometimes it will jump back and forth a few times and other times its almost like it drops into neutral. This problem only seems to rear its ugly head in high humidity.

I kinda suspect its engine related, because when I put more of a strain on the engine by running the A/C, the problem gets worse.

Any ideas on what could be causing this to happen?