Hi,

Studio 192, using UC. Studio One is not running, nor any other DAW.

Running Windows 10 x64. All drivers and software, including the OS, are up to date.

I run an RCA S/PDIF cable from the 192's S/PDIF out to its S/PDIF in. The goal is to capture the S/PDIF input in a popular screen capture software through the WDM driver. This actually works! I can record the S/PDIF input. My question lies somewhere else entirely. I only mention the end goal to give the full perspective of why I'm trying this approach.

The "problem" is that when I set the S/PDIF output source to a specific mix in UC, I still get a signal from the S/PDIF out to the S/PDIF in, even when the selected UC mix is muted, or that its fader is all the way down.

So here's the setup in UC:

1. I set the S/PDIF output to be Mix 1/2.
2. I mute the S/PDIF input in all mixes, except the Main Mix.
3. I select the Main mix as the source for Headphone 1.
4. I plug a microphone in the Mic 1 input on the 192.
5. I mute the Mic 1 input in all mixes except Mix 1/2. Mic 1 is also muted in the Main mix.
6. I mute the S/PDIF input in all mixes, except Main. This avoids a feedback loop on Mix 1/2, and ensures that it's not "bleeding" into other mixes.
7. I mute all the DAW channels in all mixes, including Main. This should prevent anything coming from any software (right?)

So, my line of thought is that the microphone is only enabled in Mix 1/2, which sends its signal to the S/PDIF out. The S/PDIF input is only enabled in the Main Mix, and the Main Mix is sent to Headphone 1.

I can clearly see activity on the VU meter on the Mic 1 and S/PDIF input channels, but strangely, even if I mute Mix 1/2 (the S/PDIF output mix), or move its fader all the way down, BOTH VU meters are still showing activity.

Now, my current understanding is that if Mix 1/2 is muted, Mic 1 should not be audible on the Main mix through the S/PDIF out/in, but I can still hear it very clearly. It doesn't appear to be crosstalk or bleeding.

It almost seems like the S/PDIF output bypasses Mix 1/2's mute and fader. I tried the same setup with different mixes in UC with the same result.

What's even more puzzling, is that even if I mute the Main Mix, or slide its fader all the way down, I still get signal on Headphone 1. Could it be that the routings in UC are pre-fader on all Mixes' final faders/mute buttons?

Could anyone test and confirm on their 192? Is this the expected behavior?

Thanks + regards,