Can you post the output ofaplay -l aplay -L
Use alsamixer and make sure the audio is not muted and/or the volume is set to something like 50% to hear something.
Tried AlsaMixer although I was a bit confused to how it worked. It was set to 66% with HDMI listed at the bottom. I pressed F3 for [Playback] thinking that was to test the audio but again, nothing coming out of the TV. I've double checked that it's not muted and the volume is turned up to a reasonable level.
I'm confused on what you thought that would be required. I think the noaudio option is clear enough on what it does.
I'm completely ignorant to computing, so when I was looking for a fix to the visual tearing through the kms video driver, every example code I saw online for that driver included the noaudio line. I felt it was best to follow those examples to the letter and not remove it, even though it stuck out as odd. Because it never interfered with my audio playback, I didn't think to question it afterwards.
EDIT: My apologies, I'm actually going to have to pack this in for now and return to it tomorrow. Fingers crossed for better results and a clearer head!