WiiM is closed hardware and works OOTB, however Volumio Motivo is superior in every and each way (my personal opinion for that matter).
When comparing apples with pears please take into the consideration that Volumio devs are working on bringing latest kernel and build solving issues with and beyond HiFiBerry DAC2 HD. Perhaps engaging with testing will produce better outcome:
Directions taken by community members are their private views, expressed freely, where