Does anyone use music server thingies such as Roon or Plex? I am using Plex at the moment but although it has some good features it can be a bit flakey, particularly playing nicely with my Sonos system. Roon is more recent, is a lot more expensive than Plex but is supposed to offer great navigation and discovery possibilities. It also operates differently from Plex, in that you control audio output (eg to Sonos) from Roon itself. It would be useful to hear from anyone who has experience of these services, particularly Roon.