Have a 2003 Monaco Diplomat with a Thetford Aria Toilet. When we travel across county it sometimes will just start flushing on its own. It has overflowed twice. It seems to be related to altitude but not sure. Just wanted to know if anyone else has had this problem. Talked to Thetford and they say replace the control board but would not tell me if it was a on going problem. My email is lee.ellis@comcast.net