analog

The pipes run in the attic in such a way that when water flows through them, the movement of the pipes on the wood sounds exactly like someone pacing back and forth, right above my kitchen area.

It freaked me out a bit until it'd happened enough times that I realized it happened every time I flushed the toilet near my room... once I had that thought, I stood there and listened to the "walking" go away, then went anf flushed again and heard it start back up. So, no ghoasties in the attic. I'm sure there's something you're missing that's causing the "walking" sound... good luck finding it, it drove me nuts until I found mine out.

That said, i'm deathly afraid of basements. *shudders*