We’ve tracked down a rather complex set of steps that might cause this, and two separate bugs (one Roon’s, one Meridian’s) that were involved.
In order for this to happen, first some residue would have accumulated within the system, either as a result of network connections to going up/down or (more likely) zone transfer operations involving the Meridian zones.
Then, playback would have been terminated by putting the Meridian hardware into Standby, or switching to another input on an 800 series device without touching the transport controls in Roon.
That brings us to Roon’s bug: crashing while processing the “you’ve lost your source” message from the Meridian device and continuing playback. In all likelihood, Roon, forgotten, but still happily playing audio, kicks off radio mode.
Eventually, radio mode arrives at a track with a different stream format, which causes it to end the stream to the Meridian device and begin a new one.
The Meridian device says “Hey, new format. Uh oh, my source isn’t active. Better fix that” and sound starts coming out. If you have mostly CD quality content, and a relatively small proportion of High-res, this could easily take several hours or more.
(In the protocol spoken between Roon + Meridian, there are separate commands for “start an audio stream with format X” and “wake up the hardware and make sure that the ID41/MS200/whatever is the current source”–we do not expect the “start an audio stream” command to mess with source selection or pull devices out of standby, and we have confirmed that at the time of spontaneous noise, no “wake up” command was sent by Roon).
So Roon did bad by not terminating playback on standby or source selection. And Meridian did bad by waking up speakers as a result of a format change.
Roon’s side is fixed, and that fix will go out in the next release.
We don’t know whether Meridian will view their part in this as a bug or not. It’s conceivable that Sooloos depends on this behavior.