It seems there are total 5 parents. The multi zone speaker volume one is just one of them.
https://www.theverge.com/2022/1/6/22871121/sonos-google-pate...
I'm not defending any of these, but in general all Software patents are like that. Most of them are obvious solutions to the problem one is working on. It's just that one person/team works on a problem before another, comes at one of the obvious solutions and gets to file the patent.
Due to this a large number of software engineers hate software patents.
Edit: having said that, I will also refer to @samwillis's comment in this thread, https://news.ycombinator.com/item?id=29841653, as to why some of this may not be as obvious as it seems on first look. And, the fact that Google had partnered with Sonos (again per that comments).
IMNAL, but per my understanding, there is a major difference between patent infringement and willful patent infringement. Which is why a soft engg should never read patents, at least not in the areas one may work at some point in their career.