I think it started yesterday or the day before, but on idle, and cruising my car is now emitting a whining sound.

I opened the hood and checked out where it was coming from, seemed to be coming from a bit behind the front camshaft sprocket (not under).

All the timing shafts and belt looks fine, it sounds like an open gas pipe from inside the cabin on idle and cruise, but more like a whirring sound when your heads under the hood.

was serviced around a month ago last

any help would be appreciated

EDIT**
to be more precise, coming from behind the left intake camshaft sprocket