imac no sound from input

I have a new imac here with a sirius radio plugged into the rear input jack, in bootcamp windows 7 i can go to the sound bar and adjust the line in jack and i hear the stuff fine, but on the mac side (lion) I dont hear anything, what is odd is I see within the sound area / input the meter jumping as if its there its just not coming out of the speakers. I tried both line in as well as internal mic but neither seems to make a difference that meter jumps but no sound from the mac of that inputted sound.

I also for kicks started garage band again saw meters jumping hit record and saw a line of stuff recorded, played that back and sure enough its my sirius radio and i can hear that playback, so i know I am close but everywhere I look under sound and everything I check or do none of it makes the sound come out of the imac speakers for me.

I am pretty new to mac here but figured it's gotta be something simple I am missing or not doing...

Bill

 

in garage band bottom left corner i did find a MONITOR button that allows me to hear the content without having to hit record and listen to what it captures (in silence as it captures) but now I can hit monitor hear it as it captures it, but once I close garage band again i am back to silence even tho in the sound settings i can see the meter jumping on the line in part of input...