I did not get any sound on any site. I tested the sound on https://www.onlinemictest.com/ and it worked on Chrome, but not in Brave. I checked the Site Settings Sound and it is not denying sound for any site. (Allow sites to play sound).
One possible explanation: I am using Linux Mint 20.1, and I installed PulseEffects. Since then, the sound is muted. Maybe it is a coincidence because I uninstall the package and the problem remains.
Any ideas on what is going on?