Hello! I have a problem: My MidiKeyboard is connected to my Macbook but i get no audio signal on Logic pro X while playing neither can I record. Usually it does work only now it doesn't! I really can't figure out the problem can somebody help me please?

>> Usually it does work only now it doesn't!... It's hard to even guess without more detail than this (system configuration?, hookup details (audio? MIDI? USB)?, Logic setup?, etc).. How is the keyboard connected to the computer? Does incoming MIDI data show in the MIDI In display in the Logic header? How is Logic configured for live playing/recording? Without some detail all I can offer are a few general-purpose suggestions.. - Do a hard shutdown/restart - Check connections; re-connect the MIDI keyboard - Check the AudioMIDI Setup utility (Applications>Utilities); try the "Refresh MIDI Setup" command