PRV Move Tool Went On Vacation

I was in the piano roll view moving notes around.  I had switched to the move tool since that's all I was interested in doing.  At one point, the tool became non-operational.  Hovering over a note did not result in the mouse cursor changing to the ready-to-move indicator and clicking and dragging didn't work when the mouse was properly positioned to do that.  Switching back to smart tool allowed me to move notes, but I could not get the move tool back to a working state until I restarted Sonar.
 
Is this something that anyone has seen prior to X2 or have I encountered a new bug?