XML structure of event data.

I'm testing code that receives and processes event message from a service in a SONOS device.

In the spec that payload is described as XML, yet in the received message it doesn't quite look correct, take a look at this fragment:

As you can see there is no standard XML line of the form <?xml version="1.0"?> which should precede the <e:propertyset> stuff.

This is not an artifact of a processing bug in the recipient logic either because WireShark also shows that this XML prefix is absent.

I guess this is valid but why does it differ from the spec? (This is present in the specs for UPnP 1.0 and 1.1).

Thanks

PS: This seems to be the case for other devices too like Broadcom routers etc - so is not specific to SONOS.

Also I used to write data feed handlers for stock exchanges and service providers (like the Financial Times) where I learned to make sure any detail like this is understood before assuming anything - hence my apparent pedantry!