sound is not working
Hi everyone. Today I tried to watch a video on my computer, and there was no sound. So I clicked the volume up button, and it doesn't change the level (there's a small "no" sign, the circle with the line through it, under where the volume level should be). In the menu bar, the volume control is now a light grey and I can't use it. Same with in system preferences. Any ideas on how to get volume to start working again or why it stopped? Thanks for the help.
MacBook Pro 15″, macOS 13.0