If you are asking is there a way to permanently turn off the "Expand Track Layers" ( most of us call is A&B track editing), I don't think that it can be turned off permanently.
If you turn it on accidentally, then right click on the track -- then "Expand Track Layers" will toggle this feature on and off.
This is also called "expanded edit mode" .. What might be happening is you are accidentally entering this mode. Here's how: " .. You can also double-click an event edge to enter expanded edit mode.. "