I don’t know that the way S2 handles room selection is ideal. (The following is all based on having S2 set to ask me what speakers/rooms to play on after “a while.”)
When I select something to play, the speaker/room selection card pops up and asks where I want to start playing my selection. I have a Play:1 in the kitchen and a pair of Play:5s + Sub in our living room, all grouped as my “Main Floor” and another pair set up as my “Upstairs.” If I was previously listening to music using Main Floor, the card still has those 2 speaker sets individually selected, but it does not seem to remember that those 2 speakers are also a group. (Main Floor shows as unselected.)
Things are further compounded if I go to select Upstairs. It simply adds my upstairs pair to the 2 “ungrouped” speakers that were previously playing. On top of that, if I truly did want to play music across all 4 speaker sets, that would actually be my entire Sonos set-up (thus, “Everywhere”) except Everywhere does not get activated.
I feel like S2 should know when you select all of the speakers of one group and should override the individual speaker selection with the defined grouping. Grouping literally lives above the individual speakers which would denote that it takes precedence over selecting individual speakers.
While I’m not crazy about having to deselect the group that was previously selected to play music “after a while,” I get that that’s probably (marginally) more intuitive than if selecting a new group deactivated the last played group. (Honestly, if that group/speaker selection is going to pop up “after a while” it’s really asking, “Hey, where do you want to play music?” and should start cleared. That we can now group rooms and speakers has reduced the number of taps for some configurations, so the need to remember is likely less important. But I know that isn’t how it has historically worked, so I don’t expect that change to get made.)