I think they don’t offer any support, since they don’t sell these things anymore. My Chromecast audio still just works though.

I have used a hifiberry before and it works fine. I am not sure what the ‘best’ alternative udget device would be, but I am also using a Chromecast audio without issues. It is smaller and cheaper than a hifiberry. Sadly, they were discontinued a while back, so you would need to see if you can find a used one.