Hi im new to sonar and im trying to understand why my comping dont work. Ive read that comping was suposed to automaticly mute my my previous lane but it does not work! I tried lots of stuff ive seen on other poste but i cant make it work. My comping is acting exacly like if i was on sound on sound! Any idea ?

Maybe the video introduction to X3 Comping might help it is on this page

cWell thas was really helpfull for lots of stuff but still dont help for my probleme ! My comping dont mute automaticly the old.tracks in playback mode .They all play at once like in sound on sound

I think you have to switch record modes (right click the record [red] button in the transport).

My record mode is already on comping

Just to check the expectation thing...... You are hearing previous takes playing back from the track you are recording into. Is that correct?
 
If that is the case I would try a re-install and if that doesn't fix it contact Cakewalk support. AFAIK the only setting that should affect that is the "Comping" record mode. If you already have that selected something is awry somewhere.

Your correct .thanks ill contact them