Carbon by itself is not noisy, but carbon frames tend to amplify any sounds made by the other components. I ride a carbon Trek Y-Foil, which has a large carbon frame section that really resonates. You should hear the normally loud Rolf/DT freehub on a Foil frame - sounds like a machine gun.
When I first put the bike together, I had a creaking sound from the BB - turned out it was the crank arms just a bit loose. A couple of successive tightenings eliminated that.
If greasing the BB bearings makes your creaking go away for a while, it may be time to think about replacing the BB - they aren't that expensive.