Back in October I noticed that I had no HDMI audio when running kernels starting from v4.12.0 on an Intel Compute Stick model STK1AW32SC (Cherry Trail) and wrote about how to fix this.
Unfortunately that fix no longer works on Ubuntu's latest ISO: Ubuntu 16.04.4. So I've spent time looking into it and created a script to fix HDMI audio though 'sponsored community work'.
The fix is sponsored by storeanalytics.de and can be downloaded from here.
To use the script to fix a running system first download it and make sure it is executable ('chmod 700 fix-STK1A32SC-and-STK1AW32SC-hdmilpeaudio.sh') then run the script it as root ('sudo fix-STK1A32SC-and-STK1AW32SC-hdmilpeaudio.sh'). Finally stop PulseAudio (pulseaudio -k) and restart it (pulseaudio --start) to complete the fix.
Now playing an audio file on the default device with 'aplay /usr/share/sounds/alsa/Front_Left.wav' works together with sound in Chrome and other applications.
The advantage of the fix being a script is that you can use it when respinning an ISO with 'isorespin.sh' (using the '-f' option) and automatically fix HDMI audio in the respun ISO for use on this device.
Please donate if you find my work helpful using the following link http://goo.gl/nXWSGf.