I have just bought a guitar oriented USB sound card - BEHRINGER GUITAR LINK UCG102 with the Guitar Combos virtual amps software. Though there is "Suitable for MAC" Finger Icon on the box, the card doesn't work on my IMac 20' Alu C2D with OS X 10.5.3. In the System Prefs -> Sounds, I can see the card, and in "Inputs" signal level indicator shows that card is working properly, however there is no output sound at all. The software provided with the card doesn't work at all. The Guitar Combos soft seems not getting any signal from the card. In the application preferences the input options shows "no card detected" (or "no card conected). I have also tried the Audacity, and I can record the guitar without listening to it through the IMac speakers, but it is raw clean signal without any effects or amp simulation (the signal goes straight from the guitar to audacity avoiding Behringer's Guitar Combos software). That means that I can listen to what I recorded. Is it possible to make it working (Behringer Guitar Combos + Audacity/Garage Band +OS X 10.5.3? Is it possible to have the sound played through the IMac speakers, or do I need headphones? I am about to give it back to the shop, but I need simply recording hardware now. P.S. This is my first post on the forum, so high everybody.