I've got 3 Pi based streamers on my network. Two are running hifiberryos and on runs Volumio. I use BubbleUPNP to control playback and they all have Dac2HS or Dac+ fitted.
If I want different things playing in different rooms, there's some odd behaviour:
If I start the volumio device running first, then change BubbleUPNP to control a hifiberryos device, it works fine.
If I start play from bubbleunp on a hifiberryos device, and then select control for another player, the hifiberry os player pauses. So I can't control more than one at a time.
Any ideas please?