Originally Posted by Aeroplane
I had the same problem a few months ago. After a thorough investigation of the bike, it turns out it was the front hub.
It had some trashed bearings and the cones were shot. Now it's my spare wheel and I run cartridge hubs.
OP, if it's a loose ball hub, there's probably some grit that has found its way in. It's amazing how loud it can be. Check it out before the races get trashed.