Steven here is the full log file, my Sonos is at the address
http://192.168.1.31:1400.
https://dl.dropboxusercontent.com/u/6747852/UpnpErrorLog.datAnd the part you asked for :
97604; 23 getxmldocument - 72,84,84,80,47,49,46,49,32,50,48,48,32,79,75,13,10,67,111,110,116,101,110,116,45,84,121,112,101,58,32,116,101,120,116,47,120,109,108,13,10,84,114,97,110,115,102,101,114,45,69,110,99,111,100,105,110,103,58,32,99,104,117,110,107,101,100,13,10,83,101,114,118,101,114,58,32,76,105,110,117,120,32,85,80,110,80,47,49,46,48,32,83,111,110,111,115,47,50,56,46,49,45,56,51,48,52,48,32,40,90,80,83,53,41,13,10,67,111,110,110,101,99,116,105,111,110,58,32,99,108,111,115,101,13,10,13,10,,len=0,text=HTTP/1.1 200 OK
Content-Type: text/xml
Transfer-Encoding: chunked
Server: Linux UPnP/1.0 Sonos/28.1-83040 (ZPS5)
Connection: close