I don’t know if it also happens to you, but I always have this fear (not only the equipment but also the whole freaking house).
I have two Synology NAS devices and one “custom” server (just a PSU, a Ryzen CPU, two RAM sticks and a SSD).
Everything is grounded, on a compliant safety electrical installation, but I don’t know… I’m maybe paranoiac by nature.
My biggest doubt is about the PSU. It is a certified PSU (from Be Quiet! IIRC), that has more than enough power (500W).
About 6.5 years ago, we had a cheap power splitter, turning one molex into 2 sata power cables, short out and catch fire inside the server, in a rack, in the DC. It melted the drive it was attached to, but the server didn’t even power down. Just looked like a drive failure until the tech got out there to swap the drive. Swapped the connector with a better one, and the drive, and put it back in prod. It’s still in prod today, though I’m decomming it.
Things might catch fire, but there has to be flammable material close enough for the fire to spread to burn down the house. I’m building my own soundproofed real with fire resistant sound proofing materials. Maybe I’ll post something about it when it’s done.