Asking for a friend: Car - BMW e46 Auto...

Last couple of days it's developed a loud ticking noise fron the enigine... It's definitely relative to engine speed I.e. If you rev it the tick gets faster...

First thing I thought of this morning when I heard it was injectors... However it's not like my injector ticking as it sounds like only one is doing it (all of mie tick so it sounds regular)... There's no other effects in terms of drivability etc either, just a noise.

Maybe a lifter? (Not very knowledgeable about this to be honest)

Any other Ideas? I don't think there's been any work done lately but can get more info if needed - please just ask!