Can only hear sound of the element I'm looking at

Hey, I’m running Cubase Artist 8.5 and I’ve just run into an issue I’ve never experienced before. Since around an hour ago, unless I’ve got all piano rolls closed and all audio waveforms closed, I can’t her any track except the one I’m looking at. So if I want to make some changes in the piano roll while the rest of the track is looping, I can’t hear anything except the track that I’m looking at the piano roll of. This doesn’t stop me doing anything, but it does slow me down a lot, so if anyone has any solution, I’m interested. Thank you.

You most probably have Solo mode on your Editors activated an your focus is still active on them. You can turn that off in the upper left corner of each Editor. There is an S in a Circle.