Midi won't playback in Logic Pro

Are you expecting to hear the sounds from the MX88?

If yes, and you're using an external MIDI track, the sound is coming out of the MX88's Headphone/Audio jacks.

Since MIDI is only performance data, (like a player piano roll) it simply plays back the performance data to any MIDI Instrument.

Are you using the MX88's built-in USB connection or legacy standard MIDI In/Out cables?

In Logic's Preferences/Audio (General tab) do you have Software Monitoring enabled?

>>So let me take a step back, can that not be done through a MIDI cable?

Now we're getting somewhere. No, it can't.

MIDI is performance data from the keyboard only, the note you played how hard it was struck (velocity) how long the note was held....etc, but not audio. MIDI can play any instrument you channel it to.

The way you have it setup now, sound is coming out of the MX88, if you have a pair of headphones, plug them into the MX88 while playing the MIDI track. So, you have to run the Audio outs of the MX88 into the interface. Then, you can set up a MIDI track and a stereo Audio track. Record the MIDI part, edit the MIDI to your satisfaction then enable record on the audio track and play back your MIDI track. Then the MX88 output is recorded as a Wav file. There's another way to do it using an "External Instrument Plugin". But I won't go into that now.

MIDI is like the piano roll on this 1927 Gulbransen player piano.

https://www.youtube.com/watch?v=ydcRAMZl0l0

My question is... are you wanting to use the MX88 sounds or are you playing a Logic software Instrument.?

If it's the MX88, the sound will be coming out of the MX88's audio out or headphone jack. Then the audio out of the Keyboard must be plugged into the Saffire's Inputs.

MIDI is not sound, that is clear, right?

What are you using as the sound source? Is the MIDI track playing an internal Logic Instrument or an external synth.

What instruments are you using.