Figuring out a knock on the front of a clio

Hi

I know theres loads of posts about suspention knock on these Clios, and mines no different. But I couldnt find any with the same symptoms.

ok, imagine caps on.. I accelerate I get one knock, take foot off throttle, put back on (forcing a jerky motion) no knock, and repeat. Touch the brake, and it knocks once, keep tapping brake (forcing a jerky motion) no more knock..
so mixing it up, accelerate (knock), brake (knock), accelerate (knock).. you get the idea :)

If I approach a speed bump and coast across it, its as smooth as non lumpy custard.

I took the wheels off, up on axle stands and had a poke around. I cant find anything obvious apart from one track rod end rotates easy by hand but had no up/down movement when prying (broke?) and one arb bush (droplink type) a bit gnarled on top. the inner arb bushes dont look good, but theres no movement in them.

Gonna go buy the arb bush in a few hours, but could the strut top mount have this effect? or should i focus more on the track rod ends? Also I changed the dogbone this morning, but that was to stop the gear stick partying on :)

cheers

Figuring out a knock on the front of a clio