I went back to edit the song I've been working on with some fresh ideas. I wanted to make changes by deleting some recorded clips and record some new ones but they won't delete or mute in Sonar Platinum.  In the take lanes when I press delete, they look deleted but I still hear the clips.  When I press delete or mute in the track view, nothing happens. What am I doing wrong?...please help.
 
Happy 4th of July!

What happens if you you mute the track itself? 
 

Do you remember if you recorded the originals clips (and additional take lanes) in "Comping" or "Sound on sound" mode?  I had what sounds like a similar problem awhile back, and the mistake I made was recording in "Comping" mode.  I should have used "Sound on sound"...I had to start over it got so bad.

Is it possible you duplicated the original track at some point or otherwise have the same audio in multiple tracks?

right click on the clip, choose unlock- delete it.

Thanks for the replies guys...much appreciated.  Yes chuckebaby, I did figure it out that I had to unlock the clips in order to delete in comp.