I'll ask again:

Can you provide a video of the noise? This will go along way toward helping you sort out the issue. There are some very astute members here, but diagnosing without video is like chasing ghosts.

With the idle speed and noise, it could be a stuck EGR. My earlier suggestion of oil pressure is still a remote possibility, hopefully a wrong one.

Also, what weight oil are you running? - Minus the additive.