Having an issue with my surface controller. The slider control on Alpha Track will move when I move it onscreen with mouse. But when I move the slider on AT it will not respond on screen. all the other input seems to work but not slider. I've tried resetting everything and recalibrating unit but to no avail. Any help would be welcome.

Thanks 

You probably already checked this, but I was just wondering if you had "channel aftertouch" enabled in the preferences.

also, check the configuration of the controller in preferences to ensure you have midi checked both input and output.

All of the above, AND make sure you've selected the control surface in and out port under the Control Surfaces section of Preferences/Midi.
 
I've only recently set my Alphatrack up again after a few years of dust collection!

BTW, my AlphaTrack works fine with all the versions of Sonar back a lot of versions. I'm not sure exactly how far back. Was it designed to work with 8.5 and the Sonitus EQ? Maybe that was it.

Thanks for your suggestions unfortunately none of those solutions work. It's sending out a signal as I can start, stop, go thru tracks, But the slider and also the touch pad do not respond. Very frustrating.  

Sounds weird, maybe she's broken!

Funny think I hooked AT to my lap top and it worked fine. Thought it was a USB issue but tried some other ports on Studio Computer and same problem. :-(

Perhaps you need to delete drivers for AT and re-install?

Every once in a great while I have to reinstall my Faderport drivers due to funky behavior.