Static sound feedback when muted on FaceTime

When I'm muted on FaceTime and making sound (like playing piano on mute because the voice isolation doesn't always block all the sound), a static sound appears and quickly gets louder and louder until I stop making sound, after which it goes away until I start making sound again. Is there any way to fix this problem? It gets quite annoying, especially while practicing. Happens on my 15 pro and my 11 pro max.