Tascam US-144MKii - MIDI

Hi Guys,
Just recently got myself a Tascam US-144MKii and i’ve been adding some MIDI tracks to my music, but on playback I ONLY wish to hear the MIDI tracks through my phones and not through my monitors (line out), which is currently happening at the moment. This makes recording through my microphone impossible because of bleeding. I haven’t got an external MIDI device which I am using, I am just using the virtual keyboard and drums that are provided on Cubase LE5. I hope someone may have a solution that they can provide me with.



Software: Cubase LE5
Monitors: Fostex PM0.4n
Interface: Tascam US-144MKii
Microphone: Rode NT1-A