Ticking sound over 4000rpm, driver's side

Super Tanooki

Hey guys,

I've just noticed I'm getting a clearly audible clicking/tapping sound from 4000rpm and above coming from the area in front of the driver (so kind of like under the steering column). At first I thought it was a piece of plastic in the interior that was rattling, but its sounds more mechanical than that, and it's distinctively driver's side, sort of above the foot well.

Speed doesn't matter - I can be doing 40mph in second, or ~90mph in 4th - it appears specifically at 4000rpm and gets slightly louder and faster in frequency as the revs climb. If I had the radio playing (which I mostly do) I wouldn't notice it, but I was driving silent today and noticed it there. Sure it wasn't there before - it's new.

Just FYI, it's not the clutch tapping sounds, I get that too but only at a standstill. This is more of a metal-on-metal sort of tapping, although it can't be felt, only heard.

Sorry if I'm not being specific enough, but I was wondering if any of you might have an idea what it is? Either way I'll be taking a Nissan tech out in it to have it checked out.

Oh, it's an 09, and has 7200m on it.