nlagaros
With polling off, I have been playing, stopping vol up dn next and previous on 2 zones with correct function and no errors!!
If I issue either a line-in or playlist, errors are generated and either plug-in has to be reloaded or sometimes restart sonospy. Sounds like you identified the line-in problem with names so I think it may be stable without polling. Suggestion that worked on another plug-in is to make the polling rate user settable so we can see at what rate/timing (if any) the polling is stable for a given setup.
I am very encouraged today as it is basically working as needed.
I hope after the basics you will add method to group/ungroup zones and a way to remember zone setup for announcements.
I have a lead on a zone player I let my son's fraternity house use that I may be able to get back. If so, I would be willing to send to you for testing. Would you please pm me and we can discuss.
Thanks for your efforts
Terry