USB DAC only offers 'analog stereo output'

I’m interested to find out why my cheap USB DAC (Behringer UCA222) only offers me ‘analog stereo output’ in the pavucontrol settings. I am sure it used to offer me a digital output option in the past.

The DAC is connected from a USB 3.0 port on my PC, and connects the other way via optical to my 2.1 system.

I can get audio to the 2.1 system, and it sounds good to me - I just find it odd that the PCM2902 driver for the USB DAC offers these options only. Perhaps it is just a quirk of the naming convention!

I’ve tried using USB 2.0 and USB 3.0 ports, as well as the LTS and zen kernels to see if it makes a difference, but there is not.

So, does anyone know more about this? I’ve included a screenshot of my configuration options (from the drop-down menu) in pavucontrol. Thanks in advance.

I guess no-one knows? Or maybe it doesn’t matter!

from a quick web search i find this

A DAC, or digital to analogue converter, is the device that translates digitally stored information from a laptop, iPod or other such device into the analogue sound that we can hear.

is this not what you expected?

The output from the system is digital, not analogue. It only becomes analogue when it goes through the external DAC and, as it happens, I don’t use the analogue outputs. Therefore I would expect it to say ‘digital stereo output’.

However, it may just be a case of semantics.

Well never heard of this thing until now but my understanding is it converts to analog. I would assume the conversion happens before going to output and more than likely before going into the computer.

However since I just learned about this (nothing i need want or even care about lol) I don’t know how it actually works and where it does conversions

Thanks for the reply. I expect this is more about how the option is named rather than what signal it actually outputs - I was just curious!

Usually it works like this, the USB output is digital, in the DAC it’s converted from USB to I2S and then to analog.

With my DAC it’s “Digital Stereo (IEC958)”.

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I wonder why mine is different?

I’ve wondered about this before too.

I use a USB > Optical digital interface that sends coverts the USB audio signal from my laptop into a digital optical signal which is then sent to my DAC/headphone amp combo, which then converts the signal to stereo audio.

The digital interface only outputs a single, digital stream, and yet my system offers both and Analog Output and a Digital Stereo (IEC958) option for the device, both of which appear to work equally well.

Ultimately, it doesn’t seem to matter but I would like to know the reason why.