hang-the-9 :
Do you even have an HDMI port on this HP computer? Are the speakers working as they are? What exactly are you trying to connect to what? If you look in the audio manager do you see multiple audio output options? Try re-installing the video card drivers?
I bought a HDMI extension for my computer it connects into the back of my computer in one of the slots. I connect the HDMI into the extension and then into my computer. Ive done the same with my acer windows 10 tower and it worked, with the HP one it isnt.
The speakers on the tower itself still work even though ive plugged it into the HDMI.
Im connecting the tower to the tv via HDMI, the screen is showing up, but the sound itself plays through the spekers inside of the tower.
I dont see multiple outputs i only see the default speaker which is for the speaker inside of the tower.