Most B&O speakers have an option in the app to limit the maximum volume, you should find it in the app under Product Settings > Configure > Sound > Sound Levels > Maximum sound volume
However, unlike my Stage, Level and BS2, I have a Beoplay A9 MK4 GVA that for some reason doesn't have this option.
This is quite annoying because I prefer to limit the max volume just in case. It happened to me a few times that, when using Airplay or Chromecast, due to bugs or accidental touches the A9's volume was set to 100 and I can guarantee you this is not fun at all.
Last week I could check with somebody who had an A9 MK2 and surprisingly, this A9 did have the max volume option. So now I really wonder why mine doesn't.
Therefore, if you have an A9, could you please check if you have this option and let me know exactly which version you have? Also if you would have another speaker without the option, please report...