So many items nowadays are powered by those nasty little wall warts, which in most cases are switch mode power supplies designed to a (low) price point and have almost no filtering. They are a noise source. Do some research - there may be a simple way to quiet them down - maybe a ferrite bead around their output wire.
Peter: any advice from your tech folks?
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"Do you expect me to talk?"
"No Mr. Bond, I expect you to die!"