Hi @Asmith88, welcome to the Sonos Community!
I’m sorry to hear that you’re having issues with your system staying connected. There are some issues with BT’s Complete WiFi (the black box and black disc) and Sonos which can cause association failures. As the steps and adjustments are different for each one, do you know exactly what BT router or setup you have? If you have any additional networking devices, like powerline adaptors or access points, those would be helpful to know as well.
Since rebooting your router generally fixes the issue, if you temporarily wire the Arc via Ethernet, does this prevent the system from dropping out? If so, and your network does meet our system requirements, then it may just be network settings (or something causing interference) that need adjusting.
If you’re not sure on how to change or adjust your router settings, I would recommend contacting our support team as they have the necessary tools available to make those for you and help troubleshoot this issue further.
I hope this helps!