Since this problem can be caused by a settings or software issue, the first thing you should do is restart the computer. The following are the most effective ways to fix Windows 10 HDMI not working issue Method 1: Restart Your Computer
Part 2: How to Fix Windows 10 HDMI Audio not working
All these issues can be fixed using one or more of the solutions we'll see in the next part of this post. Other reasons could be malfunctioning, missing or outdated graphics drives, and a software issue with the PC. If the sound is still not working, then the PC or the TV/monitor could be the problem. You can also try to use a different HDMI cable. If there is no sound, then the problem could be the cable itself or the monitor/TV. Therefore the best way to test for all three is to first connect the HDMI cable to another computer. The problem could be with the computer, the HDMI cable itself, or the monitor or TV you are connecting to. This issue can be caused by several factors. Part 1: Why is Audio not working through HDMI?
