Darren

I own a 2008 WRX STI. For the last 6 months or so I have had a knocking noise when breaking, I've had a mechanic look at it and he can't find the issue and set me back $2600 dollars.. he said it might be the lower sway arm but he can't find parts in New Zealand. He checked the bushes, bearings, breaks and calipers but the noise is still there! If I'm driving on the highway and break I can't hear it but if I'm pulling up to lights or intersections it's quite noticeable and bloody annoying.. any help or advice would be great as I don't want to sell it.. p.s I was told it's not an engine knock.