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I'm having trouble getting "Digital Rx0 Output" to, well, output.? I'm on Linux running alsa but not pulse.? There are two soundcards, an internal and a USB external.?? I can use either and/or both for "Radio Sound Output" and "I/Q Rx Sample Input" without any issues.? I also have an alsa loopback running, tested and working.?

But when I try assigning any of these alsa sinks to "Digital Rx0 Output" it doesn't work.? I put audio_verbose to 2 and on stdio it tells me it has successfully opened the device and chosen a reasonable sample rate etc it all seems fine.? It lists on the config/status window but the latency is 0, errors is 0 and Level dB is -.? And obviously no sound comes out.

Have I missed a config somewhere.? Is it relevant that on the radio/sound window the sample rate, delay etc are all editable for "Radio Sound Output" and "I/Q Rx Sample Input" but not for "Digital Rx0 Output".? It seems like I need to enable it somewhere.
Suggestions?

Many thanks
Murray
VK3ACF

Well, after fiddling with this for a little while - I got to say I agree with some other online commentators that the linux audio stack is a bit of a mess.? Maybe just poorly documented might be fairer.? It is after all, a very large and complex system.
I had turned off pulse to solve a problem with terrible latency but then I had to get the output of Quisk shared, hence using the Rx0 output.? I also tried some alternative Linux distributions and found, surprise!, that the not only was the Rx0 output working but with pulse enabled I actually got quite good latency. This was on Fedora, I had been using Ubuntu/Debian derived distros.?

And then it failed again, sigh.? Not sure what I changed but I cannot get the "Digital Rx0 Output" to work anymore. However the pulse implementation on Fedora (pipewire) seems to be working well with acceptable latency so I'm going to stick with that.
Just thought I'd document this in case it was of interest to someone else.

Cheers
Murray

Hello Murray,

The "Digital Rx0 Output" sends radio sound to a digital mode program such as WSJT. It only sends output when in a digital mode such as DGT-U. The sample rate is not adjustable because digital programs work at 48000 sps. To send a duplicate of radio sound you could use a pulse device for radio sound and then use the Monitor of that device. Or use a mixer.

Jim
N2ADR