No, I'm still here McGrath o.H., as is the house and the damn noise! Just come in from work (16:30 BST) and there it was, greeting me like an enthusiastic terrier. By the way McG, no moose in Manchester? You ever walk down Deansgate late on a Friday night?

Yes LadyJean, there are squirrels round here, lots of 'em. Horrible scrawny grey things descended from, er, a US import if I'm not mistaken! I doubt if they're the cause. They prefer being outside in the trees. Generally, I'd have thought rats, mice, even squirrels, would make scratchy scraping noises, rather than a sharp tapping. And if it is an animal, well it's been there in exactly the same place for five days now, clinging to the underside of the board, just tapping. Tapping, tapping.....

Bear in mind that there's an 18-inch deep void under the floor, so it's unlikely to be an animal trapped - unless it's big enough to get trapped in a space that size, and if it's that big, it ought to be making more racket than a sharp tapping!

Guest ("Like, durr...") - I would have followed that great piece of advice, except there's a small access door to the void from the cellar, through which you can shine a torch and see the whole of the underside of the floorboards and the void, and there's nothing to see but earth and rubble. The boards can stay put.

Yes there are hot water pipes, but they are several feet away from the source of the tapping and have always been in the same place. They do make some noise, but it's recognisable and only really occurs when they're heating up or cooling down.

Yes, the central heating's on, but it's been on for a month or so. It comes on and off during the day with the timer, but the tapping noise is there regardless.

Rapaire, I did wonder whether I could put the tapping to good use as a metronome, but whatever it is, it can't keep time to save its life. Ah, now maybe you're onto something - could it be a bodhran player? Maybe not; there are too many pauses....