+1 on the bearings. I've heard them make whirring noises or a wub-wub-wub that varies with speed and sometimes loading. It's easier on a FWD car as you can really change the load on the bearing. RWD cars are harder to vary load, it's pretty constant on ours.
I'd take the entire arm to a decent indie mechanic to have them pressed in & out. He'll be able to tell if it's the inner, outer or both.