I'm with the Devil on the strut mount bushings

 

Mine does this as well. Thought it might be the sway bar clunking around, but OP's bushings have all been replaced and has same problem. A buddy says his girlfriend's car does the same thing, and it's a normal strut sound.

It kinda sounds like the springs are shaking back and forth.

 

did you check your inner brake pad? sometimes they come out of the caliper and bangs on the rotor when you go over bumps.

 

Yeah, I just replaced the front brakes and they're tight.

 

Could this be the plastic cups that protect the shock shafts rattling around? Maybe the belly pan?