Problems with Audio Input on Garage Band

Hey guys,

Got a little problem with garage band. When I plug my guitar into my macbook, garage band doesn't seem to pick it up. I go to Garage Band Preferences and on the input drop down menu is:

System Setting
Built In Microphone
Built In Input
Soundflower (2ch)
Soundflower (16ch)

I've tried all of these and none of them pick up my guitar by itself. Also, the weird thing is is that when I change the input setting then try to go back to the built in microphone, nothing is picked up there either. The only way I can fix it is if I quit Garage Band and start it up again.

I have looked at System Preferences and the guitar is being picked on the Line In input, which doesn't seem to be possible to pick in Garage Band.

I am using Garage Band 08, 4.1.2

Can anybody help me? Its quite annoying.
Cheers

Hello Sam

What kind of Audio Interface do you use to record your guitar?

Audio interface? I believe I don't use one. Its my guitar, with an adapter, straight into the audio in port.

Try selecting "Built-in Input", then select a real instrument track (or add a new one), make sure the red circle is lit indicating recording is enabled for the track, then turn on monitoring.