Each controller associates to a particular Sonos component (via which, of course, it can control the whole system). It's just telling you which component it is at the moment. It isn't really a "need to know" and doesn't make any difference. (Although nothing wrong with wanting to know.)

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Thanks for the update John...appreciate it!

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Actually the controller doesn't issue control commands via the Associated ZP. It does so by direct connection to the player(s) in question.



The Associated ZP is the node from which the controller obtains information about the system. It's also the node through which local library art is fetched. Also, if a library scan is requested by a controller it's the Associated ZP which executes it.



The Associated ZP is the first node to respond to a controller's discovery broadcast.

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Sorry, my choice of words was rather loose. I was trying to convey the idea that the controller wasn't limited to controlling only that component through being "associated" to it. However, even if I had tried to be more precise I could not have given the exact detail provided by @ratty.

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