I have two Play5 and two Play3 in mij Sonos System at work. Only one Play5 can not connect. I ve tried everything (different wifi, system reset, back to initial settings) but it can be recognised with Mac address and then it is very difficult to connect to the system. It occurred only once with a connection, but i did not manage to do it again. All other systems work properly. I use controller S1, because my Sonos is a little bit older .

At home I have Sons Play1 (2x) and Sonos One (4x) and a Move. This works perfect. 

How can I solve this Play5 problem?