Interesting, thanks for all the feedback, I may go outside and listen here in a few, just to see what it might be, it's damn hard to pinpoint though! My IAC is brand new, and the TB looks very clean, BTW, which is the EGR valve, just so I can check it out? I'll also try and see if it is indeed the injectors, it's quite irritating, makes my car sound like a POS

I'll be back after checking this all out!