Audio lanes - can't hear audio

Just upgraded to 9 from 6.5

Normally when I record audio in stacked mode, I play back the several recorded takes by muting/unmuting the stacked lanes, listening to whatever lane is above the muted one.

Right now I am unable to hear the previous lane if there is one below it, even if that one is muted. I have to drag the audio in that lane completely away so that it’s not overlapping in order to hear the previous.

Hope this makes sense?

I can’t find any options to fix this… Anyone?