feedback in logic express 8

Hello All,

I am running Logic Express 8 on my PowerBook G4 and when I pull up a project I created in GarageBand, I get a lot of feedback. I tried going back into GarageBand and turning off monitoring and re-opening it in Logic Express again, but still get the feedback. I know one way to solve this problem is by using an external audio interface (i.e. mobilepre), but what if I don't have my audio interface with me? I have other projects where I don't have this problem and it seems to be only with this particular project. Is there something in Logic Express where I can turn off monitoring? If so, I can't seem to find it. I'm new to this DAW and I'm feeling my way around it. Can anyone help? Thanks.