The radio frequency clocks get a signal from CO to constantly correct
the time. But you have asked to solve the problem - not its
symptoms. I have not read through the long list of posts. So I do
not know if others have recommended this. Early on, many noted line
noise as a problem. And that any EMI/RFI filtering by a surge
protector is about as close to near zero as possible - and still claim
filtering subjectively. Every clock should already contain superior
filtering. To get better filtering, a series mode filter would cost
maybe $100 - for one appliance.
Do you even have noise? Get a battery powered AM (longwave) radio.
Tune to a very weak AM station (maybe up to 100 miles away). As the
radio approaches AC wiring or the breaker box, do you hear significant
noise? You should not. Better utilities even send out technicians
with radios to find that noise - an indication of electric equipment
Before you can fix a noise problem, first you must identify noise as
the reason for your 'fast' clocks. One example of how to first
identify the problem. Fixing it comes later.
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