Keyboard shortcut to disable sound card inputs?

[ElHadji]

Is there a keyboard shortcut to disable sound card inputs in Reason 10, i.e something that ticks/unticks the boxes in the preferences menu? Reason (no pun intended) I am asking is that I thought my sound card (Behringer UMC404HD) had gone bonkers since I didn't get any input on channel 3 and 4 from my Ensoniq SQ1 yesterday. Checked the audio preferences under active channel settings and noticed that the boxes were unticked for those channels . I have NOT done this deliberately so the question is if I have managed to hit a key combo that did it for me?