Submix Session x Protools
Audio I/O Setup

In the ‘Setup > Playback Engine’ settings select either ‘SubmixPatchbay 16ch’ or ‘Submix Input/Ouput 2ch’.
In most cases Submix Patchbay 16ch will give you the most flexibility, with Protools output now routing its main stereo output to Patchbay 1 +2.
Submix Patchbay 16ch - Allows audio to be routed through a 16channel virtual audio driver which can then be configured through PATCHBAY, normally used as the output from your DAW.
Sessions Input/Output 2ch - Allows audio to route directly in and out of SUBMIX SESSIONS, this should be used when routing through PATCHBAY is not necessary.
MIDI I/O Setup
In the ‘Setup > MIDI > Input Devices’ settings Protools will automatically create a ‘Submix MIDI Receive’.
RECEIVE MIDI FROM SESSIONS
Now that your MIDI I/O is set up you can receive MIDI from a user in yourSESSION. Simply create an instrument track and record enable it to activate.
SEND MIDI TO SESSIONS
In order to send MIDI to other users in your SESSION you must firstly set up a ‘New MIDI Track’ and set the output device to the predefined ‘Submix MIDI Send’.
Now other users in your SESSION should receive any MIDI data you send.