Speakers on stands are always top heavy. Wall mount them if possible.

While not disagreeing with 106rallye, I’ve been pretty pleased with the Flexson stands for the PLAY:1s I use as surround speakers, they stand up to being lightly jostled by the vacuum. But wall mounting is indeed significantly more secure. I’ve never had their PLAY:5 / Sonos Five version, but I would be somewhat concerned about their top heavy nature. 

Perhaps visiting a local store that has some on display might be an option to explore. 

With some non-Sonos speakers on stands I was worried about stability due to our cat. I made a simple wood base from an IKEA to go under the stands, about twice the size of the existing base, and clamped the stands to it.

Since you are making it you can even make it an odd shape to offer both support and fit in your space.

Many other sizes available.

17x20 $7.00 https://www.ikea.com/us/en/p/ivar-shelf-pine-70318161/

i’m going to give the flexson stands a try.  from what i’ve read, it seems they hold the speakers pretty firmly.  if it fails, i’ll just return them and mount them on the walls.  thx!!!

so i got the flexson stands over the weekend and i think it’ll work.  the stand is stable from a large base and the one is stable on the stand.  the base the one sits on, is tight enough that it won’t wobble and the power cord is tight so even if it tipped, it won’t fall over.  overall happy w/ my purchase and would recommend it if someone is looking for a stand.  only gripe is how expensive it is...

That’s the rub. In order to get quality, you frequently have to pay more. 

agreed