[SOLVED] Problem with HDMI audio output from laptop to TV

[Gnostiko]

I connected my laptop to the TV last night via HDMI to watch some shows when I noticed it wasn't playing audio like it usually does. Visual was fine, but audio was only coming from my laptop. Went through various settings and tried everything from games to mp3s, but it's like my laptop would not recognize my TV for the purposes of audio.
When I go into sound devices, whether the HDMI cable is plugged in or not, there is no Realtek HDMI Output in the devices section, even with disabled/unplugged devices ticked. It just has "speaker/headphones."
Things I have done:

• Uninstalled/reinstalled speakers
• Uninstalled/reinstalled/updated audio drivers
• Updated Nvidia graphics card drivers
• General Windows update
• Restarting laptop

It's not an issue with the TV as it plays audio fine when the Roku is plugged in. It's not an issue with the cable itself, as I have another brand new HDMI cable that I plugged in and I still get the same issue. It's worked normally from February up until yesterday when it suddenly didn't.
Laptop is an HP 15-au018wm, all drivers are up to speed. TV is a Panasonic.

 

[hang-the-9]

Try doing a system restore to a time before the issue started, you should system restore points for that.