I'm doing some recording on my old Fostex X-55 4 track and I noticed that I was having problems with the 2nd channel playing back correctly during mixdown. It was playing back very distorted and intermittently so I cleaned the channel fader with contact cleaner. At the same time I cleaned the metal tape heads on the X-55 but not the rubber parts of the path.
After completing this maintainance the X-55 is now varying in playback speed. It's usually running a bit slower than "normal" pitch with the pitch knob in its normal 12 o'clock position but it will vary a lot running between true pitch and slower and faster.
After this happened I recalled having the same speed playback problem with this deck years ago after using contact cleaner and tape head cleaner. As I recall I left it alone for awhile and then it started working normal again.
Any ideas what could be going wrong with the speed on this unit after cleaning?