Stuttering playback to USB DAC

I recently redesigned my setup and started to play with Volumio on RPi 3B+ to get most of new configuration. So, I have Marantz model 30 integrated amp paired with Marantz SACD 30n. Since I use roon and playback to SACD 30n is only supported over AirPlay (it is Roon Tested only), I come up with idea to use Volumio with roon bridge and SACD in USB DAC mode to get the best possible sound. Unfortunatelly in this setup it musinc stutters every few seconds, regrdless of type of source (WAV, FLAC, mp3). It is not related to source path, as I can play perfectly fine using attached HiFiBerry hat DAC and its output connected to analog input of amplifier. Also in previous setup it was working fine for years. So seems there is somethign wrong when using SACD 30n as USB DAC connected to RPi. I have no past experience with USB DACs, so I’m not sure whetre to start troublesooting… any advise?
EDIT: worth to mention that the problem exists when playing direclty through volumio and from roon using bridge plugin.

Please post a log, so we have more details.

First thing that comes to my mind is that the RPI3 share the same bus for both USB2 and Ethernet. So it might be that your pushing more data then the rPi can handle (hardware limits).

You can try to boot a PC from USB with the x86 image of Volumio and see if the problem is still there.

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I should have a bit more time in the afternoon to try again and pull the log from device. In meantime I only tried to reconfigure Volumio to use WiFi instead of Ethernet, but ity did not helped, exactly the same symptoms. I guess WiFi controller might also be using USB bus?

Yes.

To have glitch free playback on USB you should use something different than the PI 3. Either a PI4 or any other SBC, or PC will work

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I think I agree here. The RPI3 is prone to audio stutter on its USB port. This is discussed in GitHub. But some S/W seems less susceptible so it’s not an absolute. RPI4 apparently is OK and I haven’t heard any issues with Volumio and a USB DAC

OK, got it… Another idea (since poor RPi ailability/pricing is the issue); could using HiFiBerry Digi+ or Digi 2 Pro HAT with TOSLink connection to DAC overcome limitation of RPi 3? Should I expect any bandwidth limitation in such config?