Hi Lothlorien,
What kind of a sound is it? Is it a tone or is it a rattle or thud noise?
Some of my keys got so they would rattle when
you slid your finger off them and released them sharply. With the sound shut clear off when you slide your finger off a key you should hear a lite thud of the key coming back again a mat. If its a rattle it's plastic again plastic! This is probably not the sound your hearing, but I tried anyway.
Kind Regards,
Nobby




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