95 s14 ka24de engine noise
 

Alright 180k on motor
compression numbers:
cyl 1: 178
cyl 2: 180
cyl 3: 180
cyl 4: 179

tested with snapon comp tester.

Ok so to the point of this thread, 95 s14, ka24de bone stock, automatic. shes my daily 20 miles a day.
Im hearing this knock type noise coming from underneath the intake manifold, noise is at idle only, I don't hear it get louder as I rev up or while driving. I put a stethoscope to it, still can't pin point where this noise is coming from. I've noticed my alternator belt is a bit "wiggly" while vehicle is on. My initial thought was maybe the bearing in the alt pulley is going out, i have yet to isolate the alternator but now after listening a million times my good ol' brain of course is thinking the worst of the worst. I've heard timing guide noises this doesn't sound like it. car runs great, pulls, shifts fine, starts up without any hesitation, no oil consumption, no smoke, no coolant consumption. Maybe someone with more experience can point me in the correct direction?

heres a video/sound clip.
https://youtu.be/4dqqiRPMTqM

I appreciate any help.