Split audio and video between HDMI and DP/TB ports on Intel NUC

1st Official Post

    I recently installed the latest stable version of LE on my NUC7i5BNK. Before I go down the road of trying every cable and BIOS or software setting I can think of, does anyone know if it's possible to send audio (including pass through) out the HDMI port with little to no picture, and route full 4k video out the DP/TB port (or vice-versa)? The fundamental problem I have is my receiver is old, only supports HDMI 1.3, and it doesn't support ARC or 4k, while my TV is much newer, but only supports 2.0 audio over the TOSLINK return. For music purposes, I'd prefer the TV off much of the time anyway.

    Any help would be appreciated. Thanks.


    --- Carl

    Yeah. I bought a fancy HDMI splitter + switch when I first got the set (an HDFury). Trying to make it play nice with my Harmony remote, TV, and receiver was an exercise in anger management. A simple splitter might not be so bad.

    I thought it might be an oddball request, but it actually seems ideal on devices with multiple outputs. (Not to mention, since I sometimes boot Lakka on the device from an external drive, not having the latency hop is nice for gaming - even if I did have the latest receiver.)

    Thanks anyway.

    --- Carl

    Edited once, last by carlalex (March 24, 2020 at 2:18 AM).

    Quote from Da Flex

    He will not benefit from selecting a separate audio device, because HDMI is his only digital audio output on the NUC.

    The NUC does not allow to use Thunderbolt as an audio-only device, so it's not available as Kodi audio device.

    TB doesn't have to be the audio device. TB3 should be quite capable of displaying 4k video (I know, no Linux HDR right now), and use HDMI for audio with a blank screen at a low resolution.

    The funny thing is, in display options my only options are DP1 or default (The video is actually connected to HDMI - and works). And for audio devices it only works when the DP device is selected, not when any of the HDMI devices are selected (again, I am actually getting sound from the HDMI port). BIOS is configured for HDMI primary, TB secondary. This was also observed on this thread.

    I gather that the naming is an artifact of the internal LSPCON architecture. I don't care what the devices are called. But it seems quite funny to only have one display device option regardless of what's going on with the audio devices. This may be more of a Linux on this device issue than a Kodi or LE issue.

    Thanks all.

    • Official Post

    I bet it's impossible to get A/V on TB and HDMI at the same time. So you can't grab audio from the NUC's HDMI output, and the HDMI audio splitter solution still seems to be the best. Wow, there are some crazy dependencies among BIOS, kernel and Kodi. I don't want to deal with it. That's why you live in Silicon Valley, and I'm in Germany. ;)

    In general, I don't think there is any reason that you shouldn't be able to do what I want. I pretty much do exactly that every day at work. I independently chose the content and resolution of multiple monitors connected via TB or HDMI, while simultaneously choosing which of a myrid of audio devices to route sound to which include both HDMI audio devices and USB DACs.

    Support for the quirks of this device might be another matter, which is why I asked when the obvious display and sound settings didn't seem so obvious.

    • Official Post
    Quote from carlalex

    I pretty much do exactly that every day at work.

    That's cool, then you're an expert in multimedia routing. Unfortunately your NUC is probably far away from the hardware capabilities you're using at work. To be precise, I don't think the NUC's data bus is able to stream A/V data to TB and HDMI in-sync.

    I know that other LE users failed to use an USB DAC when it's about high speed (HD) audio. LE's Linux is no real-time kernel. On most hardware HD audio can't be delivered in time to USB, so audio data will just be dropped by the system. You will run into problems like this if you try to use TB and HDMI at the same time for A/V output.