It sounds like this might be what's going on...
Using the Mute tool, you can hold down Ctrl + Shift and select audio in a lane. That will isolate (or unmute) the audio you select, while also muting the same audio section in all other lanes.
That hollowed out waveform look means the audio is muted.
Using this function is the 'official' way to do comping in SONAR.
Scott
--
Scott R. Garrigus -
http://garrigus.com * Author of the Cakewalk Sonar and Sony Sound Forge Power book series:
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