My MacBook Pro will not play sound when I connect a second monitor via HDMI. When I use the volume buttons, I see this icon:
How do I resolve this?
macOS is outputting sound over HDMI and has decided that volume should only be changed on the device receiving the sound. If you want the audio to come out of the monitor, adjust its volume directly (or connect speakers). Otherwise, use either the Volume item in the menu bar (the speaker icon) or the Sound system preference to change your audio output device to "Internal Speakers".
Try to open System Preferences -> Open Sound -> Click Output -> Switch devices to headphones or speaker.
Try running the following command:
sudo killall coreaudiod
and then restart coreaudiod like this:
sudo -u _coreaudiod /usr/sbin/coreaudiod &
This will kill the Core Audio daemon (which is a system-level process, so escalating your privileges to super-user levels using
sudo is necessary.)
I think your TV is playing the sound to change this go to Audio MIDI Setuo located in Applications>Utilities then click on the built in output and click on the settings gear located below the speakers then click 'Use this device for sound output'
I just fixed this by going into the audio midi setup. - Click the + symbol on the bottom of the window. - select create Multi-Output Device. - highlight newly added device - click gears icon on bottom of window - select use this device for sound output.
It was absolute dumb luck messing with settings but it works!