* Make sure that the Digi 001 OMS driver is in the OMS folder, located in the System folder, and that the 001 is recognized by the OMS Studio Setup. * Make sure the "Use Apple SerialDMA when available" is unchecked in the OMS preferences which are located under the Edit menu of OMS. If you uncheck it, you must restart the CPU for the change to take affect. * Make sure that you have defined an input device in the OMS Studio Setup for your MIDI. * Make sure that your MIDI device is checked in the Input Devices menu located under the MIDI menu in Pro Tools LE. * Make sure that you have the appropriate filters selected in the Input Filters menu located under the MIDI menu in Pro Tools LE. * Make sure that "Run MIDI in background" is checked in the OMS MIDI setup window located under the Setups menu in Pro Tools LE. * Make sure that you have the correct MIDI channel selected and that the MIDI track is in record enabled. * If you are not actually recording yet but want to monitor the signal through an auxiliary, make sure that Pro Tools LE is set to Input Monitor only under the Operations menu. * Try restarting the Mac again after confirming the previous steps to make sure that the serial ports get reset.