I'm having an audio issue with Ubuntu 18.04.2 LTS.

My audio gets distorted after I open some websites. For example if I'm watching a Youtube video and i open a new website with some media content. Sometimes it happens also with only the Youtube tab opened and setting the Firefox content blocking to strict and reopening the browser fixes the issue.

I have the same problem also using Chrome so is not browser dependent.

Does anyone have an idea on how to fix it?