Hi Matt!
I've recently replaced almost all my front suspension worn parts. I had a similar issue, when driving on slightly bumpy or wavy road, a loud knocking could be heard, sometimes repeatedly almost every millisecond.
When the car was driven harder it wouldn't come up however.
I've replaced the following:
Front and rear bushings in both control arms
Stabilizer linkage (I put in Meyle HD)
Stabilizer rubber bushes
Steering ball joints (the outer ones)
Lower ball joint in knuckle
Wheel bearings
New wheel hubs
Brand new left and right axles with new support bearing on right side
And I still hear the knocking noise.
The only moving parts that aren't replaced are the strut bearings and upper bushings with the plate.
After all this, I won't recommend starting to replace everything just to guess it might solve the problem. I'll be replacing the strut bearings soon, but after that I have no idea.
Maybe it's not suspension related but the plastic around the front...
