If you are wanting to raise your audio levels, you can also just copy your original audio track and paste it into another audio track. For example, if you have a vocal on Track 1, just copy it and then paste it into Track 2. In FCP 5 and 6 you copy it, then move the original down one track, then paste into the original track. In 4.5 you might have to paste it at the end of your original track and then pull down one track and back to line it up with the original. If your audio is clean, as you said it was, then you can raise your audio level significantly this way.
Hope this makes sense.
rwd