I get on a HF net every afternoon. It's on 80 meters so I usually need to run power (usually 1 KW or a bit more).
I've used this setup for years with no problems, today my XYL heard a buzzing when I transmitted.
I've checked, nothing has changed with my antenna (an end-fed) nor my radio/amplifier. The ground is still good.
Why am I suddenly causing interference?