Headphones. Twenty minutes. I had plugged them into the cable sitting beside the actual extension cable. It was connected beautifully to absolutely nothing.

Spare keyboard. Tried three ports before remembering the cable was detachable at the keyboard end too.

Desk lamp. I was preparing an unusually strong opinion about the quality of modern appliances.

These threads make me feel better about the time I cleaned my mouse sensor while the battery was flat.

I appreciate that everyone here started with a theory rather than the obvious check. A community of investigators.

The desk lamp has requested a written apology.