I'm Having the same problem, although ive managed to pinpoint it slightly, if looking at the car from the front the sound is coming from the right hand side of the engine, at the back, close to the firewall, kinda just above where i can see my o2 sensor plug, its a consistent tick tick tick tick tick, jsut like a clock thats a little fast, and it does also seem to go away when engine ahs done some work, but eventually comes back.
what i didnt think to try, was holding the rpm higher then 650-700 and check if the sound recedes, but i'll give it a go when i get home.
a friend of mine said it was defs lifters, and not to worry, but after reading this thread, it makes me want to double check my diagnosis, also, if it is the injectors, does anyone think that an injector bath would help/solve the problem, and or, has anyone actually got results from the injector bath?
oh and by the way, big end bearing noise and lower end tap is incredibly hard to mistake for a ticking, its more like rapping your knuckles on metal, or a clacking sound like some angry kid with a pair of chopsticks being a noisy bugger, ive seen cases of piston slap on smaller engines, and they make quite the distinctive sound, even if your born blind, deaf and daft, you cant miss it, maybe the daft one might, but you get my point.
im quite nooby when it comes to RB's, i know the basics like oil/filters etc, but ive never had the top off of my neo6, so i have no idea where even the plugs are!
good advice everyone btw, so helpful, and no flaming, wtf? is this a forum with real people on it?