sound – Can’t run pulseaudio, system is mute

I installed Lubuntu yesterday and just noticed I don’t have any sound output. Also, there is no widget for volume control in the taskbar and when I try to add it, nothing happens. I tried to run Pulseaudio, but nothing happened either. When I tried to run it from terminal, I got the following error:

pulseaudio: error while loading shared libraries: libopus.so.0: cannot open shared object file: No such file or directory

I’ve tried to look up what is libopus.so.0, but couldn’t find it anywhere. Someone know how to solve this? Thanks in advance!