I would like to share how I managed to fix the music drops on my Sonos system in connection with Netgear Orbi equipment:
I moved to a new place and kept my Sonos Wired Set-Up and experienced a lot of drops in the music when playing from Apple Music and streaming radio via TuneIn. I felt like Sonosnet didn't like the new place, perhaps because of the distance involved between the Sonos devices.
Then I switched to using my WiFi network on Network Orbi firmware version 126.96.36.199. It was an improvement because Apple Music streaming was flawless, however radio streaming still dropped frequently.
I hesitated to upgrade to firmware version 188.8.131.52 (loads of bad feed-back on the Netgear community forums) but release note said "Fixes the WiFi disconnection and IOT issue" and I thought why not?
Surely, I ran into issues with this firmware, too.
First advice for anybody using Netgear Orbi: Do not run Online-Update but perform the long and cumbersome manual update as described on the support site. I have no idea why Netgear even proposed online-update (via iOS app or via web interface). I can only say that it's a messy process and very frustrating, and in hindsight I would use the manual update process, as recommended by Netgear.
Anyways: Here is how all my music drop issues went away: 1/ I applied the firmware. 2/ I switched on the Orbi router first, waited until all Sonos were connected to the router. Then I switched on the satellites.
I cannot say whether the firmware alone would have fixed my music drop issues, but two days after the firmware update all my Sonos are still connected to the router and didn't reconnect to one of the physically closer satellites and everything works nicely. Netgear Orbi doesn't let you assign connected devices to a specific router/satellite, but on the other hand Netgear Orbi doesn't change the assigned router/satellite unless you move around the equipment.
Anyways ... This is what I wanted to share for anybody who uses Sonos and Netgear Orbi. On a different note: Netgear support is non-existent. Literally! The Netgear support website doesn't let you open an e-mail ticket to support, for example. The community threads are full of customer complaints about the firmware update and the absence of any Netgear representative replies on the threads. Sonos support is significantly better.