Everything seems to work fine in Sonar X2 Pro but the playback head sticks after 1 second and doesn't page or follow the music.
Don't know what to make of it.
Running X2a build 351

The playback head is actually called the "Now Time". You probably have hit the Scroll Lock (ScrLk) key on your keyboard. Its usually on the Pause key. 

I agree with daveny5, this is something that can happen and is very easy to fix.  If it's not somewhere obvious on your keyboard then try opening up your computer's "on-screen keyboard".  There is definitely Scroll|Lock button in there.
 
However, If that doesn't fix it...
What kind of audio interface are you using with SONAR?  I don't see one listed in your credentials here.  Sometimes certain driver modes paired with incorrect audio interface can cause some whacky behavior on the Now Time Marker.

daveny5
The playback head is actually called the "Now Time". You probably have hit the Scroll Lock (ScrLk) key on your keyboard. Its usually on the Pause key. 

Just to clarify, the Pause key toggles CPU Conservation Mode, which ill cause the Now time, meters and other GUI changes to update only once a second during playback, but the Now time will continue advancing, and the timeline will continue "paging" at that interval. Scroll Lock should have a dedicated key on the keyboard with the possible exception of some laptops.
 
One other thing to note is that there is also the function in Track View Options > Click Behavior for "Left Click Locks Scroll", and this scroll lock is independent of the keyboard scroll lock. It's possible to have both locked, and have to unlock both of them to get scrolling back. The Left Click Locks Scroll is disabled by clicking in an empty area of the clips pane in the track view.

I'm using Digidesign Mbox2
I tried the scroll lock and Pause|Break buttons, also the option clicks behavior.
Still doesn't page, time code stops and the now time bar isn't moving.
But it does play the tracks fine.

Could this be my Mbox2 ?
 

GuyPicks
Could this be my Mbox2 ?
 

Yup, try downloading Digi's latest standalone drivers for the Mbox2.
 
I've seen the stopped 'now time' with them before.

Seth Kellogg [Cakewalk]

GuyPicks
Could this be my Mbox2 ?
 

Yup, try downloading Digi's latest standalone drivers for the Mbox2.
 
I've seen the stopped 'now time' with them before.

well...i didn't have the  latest driver so, i installed the latest driver 9.0.2.65 and still does the same thing.
I also uninstalled X2 and reinstalled, and it didn't help either.
Just don't know what to make of it.

Hey, new plus other moderator participation now, means that the X3 is about to drop! Moderators always renew participation in forums when a new product is about to drop, or right after the products has recently dropped!
 
We'll see something new by Namm 2014 

kday
Hey, new plus other moderator participation now, means that the X3 is about to drop! Moderators always renew participation in forums when a new product is about to drop, or right after the products has recently dropped!
 
We'll see something new by Namm 2014 

Hu ?????