I have 5 different players on my LMS and I would like to monitor their activity from a network monitor software like nagios or paessler.
I have tried to follow the txt and xml suggestions in tutoriels.domotique-store.fr content 54 95 fr api-logitech-squeezebox-server-_-player-http
but no success.

Can someone help me or point me in the right direction?

A fallback plan would be count the number of player like in wiki.slimdevices.com index.php Logitech_Media_Server_CLI but then I do not know which one is not playing.