Nature, or nurture? Frankly I'm not sure.
My dad owned a TV/Audio shop - sales, install, repair. I went to the shop with him on Saturdays at a very early age (4-5). He'd work, and set me down with a screw driver, pliers, and something harmless like a broken up phonograph. While not doing that I'd just wander around the stacks of amps, speakers, TVs, or just watch him or his partner work on repairs.
That's the equipment part. I also have always liked music. My whole family did.