I have not noticed any noises yet.
He has started changing a little in just the past few weeks - lately, if he sees any motion in the room he will come about half way out of his current hiding spot and sit up on his fins. This is brand new behavior that he just recently started doing.
I'm assuming he may have reached fish puberty or something which has turned up his aggression.
I haven't been bitten yet but based on his activity here lately I'm guessing it's only a matter of time before he gets me.