Is it a time bomb? No? My heart? Could be, but no.
It sounds like an exceedingly slow watch movement. Tick…………… tick…………… Like my watch with a clear crystal on the back, where I can see the little wheel ticking the seconds. This is that, but slowed wayyyyy down in a demonstration of relativistic time dilation.
It’s the sound of my brain, working out the details of the book I sometimes call The Masters of Shipworld, but usually just the book. For a period I will call a very long time, I felt almost no forward movement. I was frozen in time, caught in the event horizon of a creative black hole. Sometimes I’ve thought of it as spinning my wheels. Sometimes I’ve thought of it as being lost in the wilderness. But now I think I have it. The watch movement of my subconscious has creaked into motion. Don’t stare at it, or it’ll stop; it only ticks when you’re not looking. Each tick is me snapping my fingers and going, “Yes! Of course!” as a new plot or character point suddenly comes into focus. It’s not always a big point. Usually it’s some little thing that makes me wonder why I didn’t think of it sooner. But they’re accumulating.
The gears are moving, even if you can’t see it happening.
Because the whole Black Friday thing really bugs me. This is more of a “Have you listened yet and would you like to listen for really cheap?” Yes, another 
Everyone loves autographed books! Especially sets of books. I know just where to start: 
The audiobook of 
For you ebook readers, my omnibus volume