For “Audio Input” choose “Aggregate Device”. Make sure “Audio Output” is set to “Built-in Output” To record more than one track at a time in GarageBand, click on “Track” “Enable Multitrack Recording” Select the “Guitar Track” and click on the Amp and select 'Edit'. You will see that input source is set to Mono 1. Garageband has a feature that I both love and hate – normalization. If you love controlling the output volume of your podcast using Garageband, you’re going to hate it. Normalization takes over on export and adjusts your volumes to optimize (questionable) for playback. Mar 26, 2009 I just bought a usb condensor mic and i'm trying to connect it to garageband (which i've never used). I selected the usb mic as the input source in the sound pane of system preferences. Strong signal there, but no signal in garage band new track. When i open the 'new track' window and select.

Click here to return to the 'Combine multiple audio inputs for use in GarageBand' hint

This will not work with Digidesign interfaces (i.e. 002, Mbox, etc).
Digi has hobbled their Core Audio plug-in so that it will not appear in the aggregation window.

To answer the question about USB and audio streams:
USB 1.1 (Or USB2.0 Full-Speed) should allow up to 6 channels of 48khz 24 bit audio, although that is using up the bus and if used often you may get drop-outs.
USB 2.0 High-Speed can get a lot more depending on the sampling rate and bit depth, but 16+ channels are possible. The same is true with Firewire 400, and of course more with Firewire 800.

I couldn't get this to work for a few days. I'd open the editor, make the new device, and it wouldn't show up in any applications. If I quit Audio MIDI Setup & reopened it, the new device was no longer there.
The problem was that I was doing this as a regular user, not an admin. I just finally got it to work by logging in as an admin user, making the device, and logging back in as my regular user. Now the regular user has the aggregate device available.
peter

Do you think that other operations in the Audio Midi Setup CP also require you to be logged in as an Admin? I'm trying to enable the rear outputs to send the audio through while the interface is recording. There are check boxes in the firepod's I/O list, but they are greyed out for me. Haven't tried it as an admin yet, though.
Too bad I could find NADA about this on the Apple or Presonus support site...

Logitech No Source Selected

I've just plugged my mac back into my interface and Guitar Rig Kontrol after recording elsewhere, but when I go to click record in the Rig plug in track, a message comes up with 'No input source selected'.

Garageband Audio Input

I've gone back and checked all the audio and project settings and it all looks exactly the same as before, and the guitar's plugged in fine. And the input bar in audio settings, set as Rig Kontrol/Fast Track out displays the signal - it seems to be 'selected'. Is there anything else I'm missing??