If the creaking is the bearings, its likely caused by contamination and corrosion to those bearings. This will likely increase the friction, making the bearing ‘turn’ less effectively. At some point the friction will begin to add load to the outer bearing race which is the part that contacts the frame. This, especially in a carbon frame, could be bad news as it may damage the carbon or, if the frame has them, the bonded metal inserts that the bearing presses into.
You might be able to pry off the bearing seals and flush with wd40 or gtg4 to remove old grease and dirt, then repack with grease and put the deals back on. This might help until you get new ones.