context menu pops up all over the place?

A popup context menu containing "Remove from Group; Clear Group; Group; Group Manager; etc etc" comes up on left-clicking the "mute" button on a track, also on the solo button, also just clicking somewhere in the track.   
 
beginning to investigate other options here, x3 seems awfully awkward

scook
Not sure why left-click causes the context menus, unless the left/right buttons are switched in windows.

Agreed...check the Mouse section of the control panel. AFAIK there's no preference in SONAR that allows switching the left and right mouse buttons.

Right

williamcopper
I think I must have gotten sonar into an unstable state somehow, that problem went away by itself.

If so, nothing like that has ever been reported before. AFAIK what associates a gesture with a particular mouse button is a Windows function.
 
In other words, I think it is extremely unlikely what you experienced has anything to do with SONAR, regardless of whatever you may have done within the program. As a result you will probably run into this issue again, possibly with SONAR or possibly another program. If the right and left buttons didn't become reversed within Windows, then I would check whether your mouse is performing up to spec.
 
Also be aware that some mice have applets that have their own preferences and that could be a problem. For example if you have a Logitech mouse, look whether an applet is present and if so, click on "restore defaults."