I know I'll probably be tarred and feathered for this one, but I recently installed this chain on my bike:
which has an all-city chain ring and cog. But it is now not the quiet whisper of a bike that it used to be. It omits a constant rattle/buzzing noise that is clearing coming from the new chain and the chain line is definitely straight. It is not overly tight, and the noise is somewhat muffled when I lube the bejesus out of it.
Could the chain just not be good for my chainring/cog setup?