Help please!!!!!!

[1greenjk]

Hello guys. I am new to recording and pro tools express. I have a iMac OS X and a Mbox mini 3G interface and for monitors I have AV- 40's. I can't hear the metronome playing and I can't here my recordings when I play them back. If I turn the volume up all the way on my monitors I can barely here it. I can here my guitar when I'm not recording and i have a good signal. I've tried everything and i don't know what to do.