Problem with micro in jitsi meet and linux mint 19.3

Good morning
I have been using jitsi meet for several years without problems, but for a few months I have had a problem with the sound of the microphone. My microphone is no longer heard, although I listen to the others and it forces me to close the browser completely (all tabs open) to be able to use it again. When this happens I have checked that for some unknown reason the use permissions of the camera, microphone and headphones are set as not allowed in the jitsi settings (but they are allowed in the chrome ones). I use Linux Mint 19.3 and the latest version of Chrome available. I have also verified that it happens to me with different headphones, clicking them on different jacks, using the camera’s microphone … There are times that it doesn’t happen and other days three or four times per conversation (we do long conversations of 3 or 4 hours).
Any idea why it might happen?
Thanks for your help