Sorry just saw this one and remembered a few FEARS:
In the old days, we used to live in a big house with a tiled roof and rafters. Dad used to have the amplifier at one end of the hall and run his speaker wires through the rafters to the other end. I remember when he switched on the amp, he used to watch the output valve carefully. He would say, if the glow was brighter, it meant rats had bitten off his speaker wires or there may be a short circuit. He would stop looking once the valves heated up and the amp got started. Could not understand the logic of the brightness but remembered him telling me this when I was a kid.
My FEARs
1) my 2 year old son fiddling with my turntable while it's playing (I usually play my vinyl without the dust cover on)
2) my 2 year old son knocking down my equipment rack, he once tried to climb it up, like a ladder
3) both my sons cranking up the volume (after all, I'm using BPL Sanyo 700T speaks and my NAD 216thx is capable of blowing their cones out of the frame)
4) my sons coming near my vinyl collection or near my vinyl record covers kept on the centre piece while the record plays, they can easily cause damage
5) kids near the speakers, my son and my brother's son have already attempted to push in the dust caps
6) wasps coming in through the window, may try to build a nest or two in my speaker's tweeter cavity