It used to work, then after updating Moode it didn't. And HiFiBerry OS gave me a ton of headache as well... I have it running right now with Moode, but it wasn't trivial for someone who really knows his way around Linux... that's his day job.Hmm... maybe you're having trouble installing and configuring it correctly? Because I can confirm once again - here and now it works for me without any problems! (RPi 3 and Digi+ Pro with System Software 20230404)
WiiM idea seems good. But are you sure it's not "messing" with your network in a way you wouldn't want? It's so damn cheap...
And when it comes to Pi and HiFi BerryOS - I know what I have!
If you're lucky / love tinkering, sure, use the Pi. But at this point I would not recommend buying a Pi and the rest of the hardware, rather than the Wiim. And yeah, that risk always exist, but you could isolate it in your network if you really want to. That's probably easier to do than to get the Pi running. Also, is the Wiim that cheap? The hardware required isn't that expensive (the DAC for example is useless). Licenses and the software cost, but I suppose they sell a ton of these. IMHO other companies are vastly overcharging, cause they can.