If the MC3+ uses an XMOS chip, then it’s almost assuredly bugged unless they’ve released a firmware update recently. And it CAN show differently based on the software used. The bug is triggered in a race condition, and Roon is very quick when switching modes between tracks. If other players introduce delay, then they might not exhibit it.
Have a look at the master thread for more details: DAC issues with XMOS usb chipset and Roon on Linux