Earlier we reported that both the Apollo Lake and Kaby Lake NUCs were suffering from an issue that prevented HD Audio (Dolby TrueHD and DTS-HD) bitstreaming from the NUC to an AV receiver. Intel has today released an update to the firmware of the DisplayPort-to-HDMI2 converter chip that is also known as LSPCon. This firmware update will fix the issue that prevented proper audio bitstreaming to a HDMI 2.0-capable AV receiver.
You can download the fix here at Intel Download Center.
Ok, so this is all good. Unfortunately the patch is only provided in form of a Windows 64-bit executable. Now I had already installed Linux on my Apollo Lake NUC, so I had no way to actually upgrade the thing! What I did was to download the free 90-day evaluation version of Windows 10 and install that on the NUC. This was quite an effort but I really wanted to have the HD audio bitstreaming working!
The documentation says that you must have your NUC connected to a HDMI 2.0 device when upgrading so I connected it to my Marantz AVR. I noticed that the old version of the MegaChips MCDP2800 LSPCon firmware was 1.56 on my NUC6CAYH and the new version after the upgrade was 1.61. If you already have version 1.61 there’s of course no need to upgrade. The update itself was simple but during the installation the screen goes black for a couple of minutes. Do not press the power button or do anything else when this happens – just wait patiently.
After the firmware upgrade a reboot was not even necessary – I just opened MPC-HC and I was able to play back all my 7.1 channel audio clips properly! It finally worked as it should.
Now, would this fix the same problem that I had with the device under Linux? I set to find out. Quickly installed LibreELEC 8.0 (A Linux distro meant for running Kodi to turn your PC into a media PC with minimal effort) but unfortunately the problem persisted in Linux. This means that the bug report here is still valid… But anyhow, good to see that the hardware itself is capable.
EDIT: Not so fast! It seems the issue is still there if you change your screen refresh rate! When I set my screen to 1920×1080@24Hz mode the 7.1 audio formats stop working again… Intel is aware of the issue, so we’re again waiting.
EDIT2: There’s an update to this saga.