Working on a new project - in X1 Producer. Re doing some tracks - audio on guitar and from one of my sessions to the next, when I go to pan two tracks left and right - they stay up the middle - the pan knob / slider out of nowhere is not changing the signal at all to L or R? It is still working ok on another project??!! Any ideas please.. 

If the knobs/sliders are moving where you want them while the playing has stopped and goes back to the middle once playing has started, the check your tracks for panning automation. It may be enabled on the tracks.

I checked that out --- no automation in place. I move the sliders and they stay there without jumping back to center- but with no affect on the output. Thanks. I may just have to break this project down - delete all these tracks and start over again - or jut open up a "new" project template and go from there . It would  be nice we could find out why this odd thing is happening.
 
Thanks !

Make sure that you're not in offset mode and the track is feeding a stereo bus or stereo master.

Gustabo --- your comment fixed me up ---- the master was not set to stereo: for some reason it was clicked to mono and I just did not notice --- fixed this in a hurry. thanks !! 
 

Glad I could help...