There are few areas to analyze in order to try finding a possible solution. We have the video and audio source (local movie, blue ray, video streaming, etc), the graphics driver that also contains the Intel® HDMI Audio driver, the HDMI cable, the HDMI AVR (audio and video receiver), and the speaker system (sometimes part of the AVR).
The original video and audio signal is obtained from the source and it is packed and encoded by the driver to be sent through the HDMI connection. In the other side the AVR is in charge to receive and decode these packages and converting them in to video and audio signals again. If the audio source is based on 7.1 surround sound and the AVR supports it, you should get 7.1 surround sound output, but what can interfere there?
The Intel® HDMI Audio driver only gets the information as it is from the source and packs it. There is nothing within the driver that can be changed to vary the distribution of the surround sound channels unless the source allows it before it is played back.
There is a possibility that the AVR is not translating correctly the information received from the NUC HDMI port or it doesn’t understand it properly. Some AVRs don’t support HDCP (digital copy protection protocol) and this generates reading problems. Also, the HDMI version of the AVR vs. the NUC HDMI can generate compatibility issues, in our case it is HDMI version 1.4a; and finally the quality of the HDMI cables being used.
Here some recommendations:
- Update the NUC graphics driver. Use the following link to download the latest version: https://downloadcenter.intel.com/download/25118/Graphics-Intel-HD-Graphics-Driver-for-Intel-NUC
- Update the NUC BIOS. Download the latest version (WY0040.BIO) using this link:
- Follow these instructions to update the BIOS once the file is downloaded: http://www.intel.com/support/motherboards/desktop/sb/CS-034522.htm
- Test different HDMI cables. Make sure they are high speed and high quality ones; we have seen many compatibility issues due to cable quality.
- If your AVR has DisplayPort support then use it instead of HDMI.
- If possible test the NUC in a different AVR
- If the problem persists this could be a problem with the HDMI port in the NUC.
In regards of the headless issues, we are pretty aware about it and we have offered different work around options which in some cases work. The most effective one is using a dummy HDMI adapter so the graphics driver detects a monitor connected.