Logic Pro Input Monitoring while Playing back tracks

Hey there,

So, out of the blue, I noticed that when I have my Input Monitoring On (on every place on logic - Settings, Menu Bar, etc), the recorded audio doesn't play back (no, the Mute button is not engaged). A soon as I turn off the Input Monitoring, the audio starts playing with plugins and such, but I lose the input monitoring....

Don't know if I was abe to explain it right...

but...

When I have a drum track and a guitar audio playing and I hit the Input Monitoring on, all I have left is the drums playing back. I can hear myself (because of the input monitoring) but not the recorded audio... and once I Turn the Input Monitoring off, the guitar track starts playing back normally.

I don't know what the heck is going on... I "Solved" the issue by using Time Machine from the day before...

Could be a Keyboard shortcut that I've accidentally pressed?