Does this happen when you move the camera on Frame 1?
On every other frame when you move the camera you create a key frame on the camera timeline so it may just be moving to key frames you've unknowingly set. (check the camera track in the timeline to see what key frames are set). However if it is happening on frame one then it may be a bug.
- TET
Animation and Video Life
The Lazy Animator - Tutorials for Cartoon Animator