So, yes….and no. 

First off, you can submit a system diagnostic within 10 minutes usually, and call Sonos Support with the diagnostic number to discuss it. The purpose of the 10 minute timing window there is, of course, limited memory on the system to store that data in, so if you wait too long, the event will have timed out already, and not be visible to the folks at Sonos. 

Second, while I kinda like the bluetooth possibility, there’s another one you may want to consider, and a couple of less frequent potential issues that are worth looking at. 

First, and most frequently, is use of “Spotify Connect”, where you give someone access to send a stream to your Sonos while they’re in your home, and connected to your wifi. The unusual aspect of that is, once that they’re outside of your home, the Spotify Connect connection is maintained, even though they’re no longer on your wifi, until such time as you play anything else (just not Spotify) on your speakers. It’s been a frequent case where someone outside the home has apparently been trying to play something on their local Spotify, and don’t recognize that it’s still connected to your Sonos. Frequently, they assume it’s a volume problem, and turn it up, since they can’t hear it playing. Which makes life interesting for you. As indicated, when allowing someone to use Spotify Connect, all you need to do is play a stream from anywhere else, and it will “break” that connection.

Second, there’s also the possibility that someone set an alarm, and it’s going off. Much less likely, but at least worth double checking the settings in the controller.

Third, and probably very remote in your case, if you’ve connected your speaker via Bluetooth to a TV, there are some TVs and/or cable boxes that turn on their audio in the middle of the night, when they’re checking for updates to their OS. Might be worth, if you can, making sure your TV is up to date. Most TV manufacturers have fixed that bug, but it’s possible that it’s still happening here and there. 

Hope this helps.  

Oh, and more specifically, you as a user don’t have access to that data in the diagnostic. There used to be some places you could poke around and see some stuff, but most of that is now closed up, due likely to security issues. And of course, people like me, who don’t work for Sonos, also can’t see that data.