The reason why your devices that are plugged into an HDMI are not correctly working is either because: The HDMI port or cable are physically damaged or bent. The Drivers for your PC are not up to date, and they are preventing a picture/ sound from appearing. You have not configured your Display to be the main screen.
How do I know if my HDMI port is broken?
If the HDMI cable, which sends high-definition pictures and sound from your console to your television, is plugged into the port but there is still no video, the port may be damaged or not working properly. Possible signs of a PS4 HDMI port issue are: A black screen or a “No Input” message.
Why am I getting no HDMI signal?
To fix the HDMI no signal problem, check for any loose connections or frayed wires. If the cable is not damaged, change the input source and enable the HDMI connection setting. In addition to this, I have also mentioned other solutions such as updating the chipset and graphics of the TV and performing a power cycle.