[Solved lol!] HDMI splitter won't send audio to both split outputs

[jaibubwan]

Just got a new cable hookup in Canada (company B). I sent the cable box's HDMI to my reliable splitter. One split goes to my PC's capture card. The other split goes to my TV.

But what I'm finding is...if both splits are connected, the audio only goes to the TV split (the capture card gets no audio, only picture). Disconnecting the TV split lets the sound go to my capture card (along with picture, which was never a problem).

So basically, the picture is getting split perfectly.
But for whatever reason, the audio only seems to go to one split.

Is this normal with splitters?
Is there any setup/solution where I can have sound going to both splits?

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UPDATE: I just tried an Android box with the same kind of splitter. That's able to send picture & audio to *both* split outputs (TV & Capture). This worked with a certain restrictive video streaming service (N).

But for some reason, it just won't work with this cable box. I don't understand why.

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FINAL UPDATE: Problem solved! I don't know what happened. I restarted my computer, swapped the splitter, unplugged/replugged my optical audio out on the cable box...all of a sudden, right after I gave up...it just magically worked! Not sure which of those actions it was that did it...but dang it got did - thank everything holy!

[Eric-jan]

Where HDMI is involved, startup procedure is also a "factor" it's all about communicating.... and then i even don't talk about .....HDCP....

[Cornucopia]

Yes, part of the startup procedure is called 'handshake". During that period, both devices enumerate what they are capable of, and they must agree upon common settings - resolution, framerate, color subsampling, etc for video, and #channels, codec, samplerate & bitdepth, etc for audio. Remember, there is likely no intervening converter (such as a scalar) which translates between them.

Your setup is made much more difficult because ALL 3 devices must agree to a common format, and without a converter, you are at disadvantage and must rely on the handshake sequence occurring in the right order, otherwise one device is left out of the conversation and is orphaned by only being able to accept the table scraps of what was commonly agreed upon without its input/consent. That's what was happening in those earlier tests.

This is why some commercial AV systems can get quite expensive, as they are handling a variety of scaling/converting simultaneously.

Good to hear you lucked out.


Scott

[jaibubwan]

Yes, part of the startup procedure is called 'handshake". During that period, both devices enumerate what they are capable of, and they must agree upon common settings - resolution, framerate, color subsampling, etc for video, and #channels, codec, samplerate & bitdepth, etc for audio. Remember, there is likely no intervening converter (such as a scalar) which translates between them.

Your setup is made much more difficult because ALL 3 devices must agree to a common format, and without a converter, you are at disadvantage and must rely on the handshake sequence occurring in the right order, otherwise one device is left out of the conversation and is orphaned by only being able to accept the table scraps of what was commonly agreed upon without its input/consent. That's what was happening in those earlier tests.

This is why some commercial AV systems can get quite expensive, as they are handling a variety of scaling/converting simultaneously.

Good to hear you lucked out.


Scott

I had this same problem a few days later. Again, I tried swapping/reconnecting all the wires, to no avail.

But this time I narrowed down the solution for this problem.

I identified that turning off my computer (and perhaps something happening overnight on the cable box) was the culprit. Upon turning the capture-card PC back on, you may have that discrepancy with the audio only going to only one splitted-device.

So once the computer with the capture card is turned on, we just have to reboot the cable box - and the "handshake" (which you've excellently explained) seems to occur and sets things right.