- Help?!?- X1 Win7 64 Suddenly Not Responding to Midi

craziest thing... all of a sudden X1 is not responding to midi... from controller, but it ill play back midi recorded. also, stand alone soft synths are responding to midi just fine - I'm sire this is operator error, that I stumbled over some setting somewhere and screwed myself... any thoughts? many thanks... at my wits end... all settings I can find are the usual, set to omni in, my controller is working on stand alone synths... just not from inside X1...