I’ve recently installed my old Play5 (1st gen) in my summer house. The speaker was factory reset and then set up on my completely new home network (via WiFi). After using the speaker for a couple of hours, and again the following day (8-10h of music in total) I was surprised to see that it had used 45 GB bandwith! Checking my router it is clear that the Play5 uses around 195 mb every five minutes (external connection) - even when its not playing!
The network is through a brand new ASUS 4G-router with a SIM-card, providing a fine connection. The subscription only allows me to use 50 GB of bandwith per month. Only a Chromecast and the Play5 (along with my phone) is connected to the wifi.
Sonos Support had never heard of this issue (odd?) and recommended that I turned off the speaker when not using it.
Turning the speaker of every now and then sort of ruins the complete idea of having a remote controlled system?
Several others have experienced this, but there is no answer how to avoid it?