Bathroom spigot screechs

'allo,

I belong to little brick bungalow in midwest, built in 1954.
Bathroom is unimproved but well maintained.

Lavatory spigots. When I turn the cold on or off, it
screechs noisily. Tiny little screech when I turn hot
on, none when it's turned off.

Washers were replaced 1-2 years ago.

What makes it screech? How to fix?

TIA,
Puddin'

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