VST instrument doesn't sound any more

Hi!

I’m pretty new to Cubase, so forgive me if I’m asking something rather basic. I have recorded a few tracks with various VST instruments. Now, after some keyboard shortcut I mistakenly pressed, one of my VST instruments is not “playing” any more. I double-checked the volume, appropriate channel, mute button, etc… But I cannot get that recorded track to play again.

Anybody has a clue? Thanks in advance!