Loki Laptop, no sound through Radeon HDMI

Question

Hello this is a brand new laptop: HP Envy x360 m6-ar004dx convertible.AMD FX-9800p APU.

Sound works fine with the internal speakers and headphone jack, but will not work over HDMI. Sound settings shows HDMI and so does Pavucontrol, along with 3 profiles: Digital Stereo (HDMI) Output Digital Surround 7.1 (HDMI) Output Digital Surround 5.1 (HDMI) Output with unplugged or plugged in appended depending on whether or not it's plugged in.

alsamixer shows HDA ATI HDMI with a single S/PDIF 00.

My older laptop also shows this, but everything works as expected, the older laptop is also a AMD APU system. I do not use proprietary drivers, and I don't even know if they're available for Loki/Ubuntu 16.04.

PLEASE HELP ME! I spend alot of time hooked up to a tv using the sound through it.

Answer 1

So for anyone else who may be experiencing this issue: The lack of HDMI audio is documented on Ubuntu's AMDGPU and AMDGPU-Pro wiki pages. As of Ubuntu 16.04, only the open source AMDGPU/amdgpu-Pro official open-source Radeon drivers can be used on newer model GPU's and APU's(like mine), it specifically notes:

"The open source AMDGPU driver does not support (for now) the HDMI audio. To solve this problem, you can install che "hybrid" AMDGPU-Pro driver from AMD."

The "pro" version includes SOME(as little as possible) proprietary blobs, HDMI is a proprietary, licensed technology, so this is probably included as one of these proprietary blobs.