Cannot get sound
iMac 27" OS 10.15.7 has no sound coming out of speakers. No Alerts, no music, no websiute sound, no Zoom call sound, etc - nothing. Only thing that has changed in the past 24 hours is the moving of my computer from the left side of my desk to the right side. Only one plug in and that's an external hard drive for saving items. System Preferences - Sound displays Sound Effects as all greyed out, Output as greyed out, and Input with no devices. I'm stuck. Help?
Richard Hayden’s iMac (5) 21.5" 2009