Here, users reported that simply turning off the monitor while the MacBook was working solved the problem for them. This is a quick workaround but seemed to work for a number of people.
Note: You may have to do some or all of the above steps to get sound coming out of your TV when connected using a DisplayPort-to-HDMI cable to your MacBook Pro.
How to Find the Wireless MAC Address on a Vizio Smart TV. You should now have audio coming out of your TV from your MacBook. If your Vizio TVs HDMI port is not working, the most successful fix is to perform a hard.