Hey @Taavi_Kald,
Thanks for the video and the extra detail, that made this much easier to pin down.
We pulled the diagnostics from your Roon Server and can confirm what’s happening, and it’s not something Roon is doing on its own.
The AV10 presents a single volume control to Roon over RAAT, tied to your “2 Living room av10” zone. What the logs show is that when Zone 3 powers on, the AV10 sends Roon a volume update carrying Zone 3’s state on that control, its range and its level, not the main zone’s. Here’s the moment from your logs, at 19:01:20 local on August 24th:
[Marantz AV 10] [raatclient] GOT
{"volume":{"max":18.0,"min":-80.0,"step":1.0,"value":5,"type":"db"}}
That max: +18 / value: +5 is Zone 3’s scale (−80 to +18 dB) and Zone 3’s fixed +5 dB level. Roon received it and updated the slider accordingly, which is exactly the jump you’re seeing. Immediately before that update, the same control was reporting the main zone correctly at −24 dB. It reverts when Zone 3 powers down for the same reason: the AV10 goes back to reporting the main zone.
Two things worth knowing:
Nothing unsafe is happening, and your volume limit is why. Roon never sent a raised volume to the AV10, every volume command from your server in the whole log window is at or below −25 dB. The Roon volume limit you have configured (−24 dB) is also still being enforced independently of what the AV10 reports, which is what’s keeping this cosmetic rather than audible. I’d suggest leaving that limit in place.
There’s a second, related symptom in your logs. The AV10 also changes its reported volume ceiling on its own, unprompted, bouncing between −24 and −20 dB within the same second, and at one point through −14 and 0 dB. It also switches its volume type between “variable” and “fixed” mid-session, hundreds of times on a busy day. If you’ve ever seen the slider briefly change shape or disappear, that’s this.
All of it points the same direction: the AV10’s Roon Ready implementation is publishing the wrong zone’s volume state on the control it shares with the main zone. That’s on the device firmware side rather than something we can correct from Roon, so I’m passing the log evidence and timestamps to our partner team to raise with Sound United.
In the meantime, if the slider jumping is disruptive, setting Zone 3’s volume mode to fixed (as you already have) keeps the audible behavior correct it’s only the displayed slider that’s affected.