Can't hear input when recording new track

I am new to PT and have been using it a for approx. 1 month and it has been working fine. Recently I took my laptop to the studio and when bring it back I can hear all playback fine but when I try to record a new track I can't hear the input. I am using Mac Book Pro, Mbox Pro, and PT 10. When I engage the track into recording mode, I can see the levels correctly displaying on my mbox pro and am also receiving the levels into my track in PT. If I hit record and play I can also record any instrument. The issue is I can't hear the instrument through the monitors. I can hear playback on previously recorded tracks with no issue. I looked up help and tried to go to my system settings under sound and adjust that. I'm not sure how to tell if my sound settings are correct or not. I also looked at the Mbox Pro settings and they look ok but am not real familiar with them to have a good comfort level to say there isn't an issue there either. Please advise.