Just wanted to share a solution.
Had problems regarding the sync between my Sonos Connect, connected with a Beoplay A9, and my other Sonos (arc, Sonas SL). The sound on the A9 came out 1-2 sec later then from the rest.
The solution:
- Open the Bang & Olufsen app
- Tap the "Settings" icon in the upper-right corner
- Tap: Settings
- Tap "Products"
- Tap your Beoplay A9 4th Gen
- Tap "Configure"
- Tap "Sound"
- Select Line-in and tick "Disable Delay"
Note: If the delay is disabled, you cannot distribute sound from the Line-in input in a Beolink Multiroom setup.
Everything went in perfect sync after that.