I had for a long time an issue with sound explosions on my sonos speakers. Volume would go instantly to 100%. Others had the same experience. It is discussed in the support forum, but the cases are closed there, so I cannot report.
The solution seems to be to use Airplay instead of the Sonos protocol. I switched and no more explosions! The only downside is an old loudspeaker without airplay support that I had to replace.
So, I bought an Sonos Move 2. It does not work with Roon on Airplay. So, back on the Sonos protocol. I assume there will be Explosions now. I will report back.
I’ve used Sonos devices with Roon, trouble free for 5 years.
The sudden jumps to 100% volume that did occur a few years ago for some folks seemed to be related to iOS devices
What are you using to control Roon?
The Sonos Move 2 doesn’t work with Roon via Airplay 2. I don’t know why.
Thanks! Well, no explosions so far. Android, Samsung or my PC to control Roon. I have not had an Apple product in house since 2001 when iTunes changed the filenames of all my music files 
so no iOS involved here!
The Move 2 comes and goes, but I think the mic is involved and has to be off.