Hi guys has anyone tried using a Gaitronics SIP extension on the 3800. I have of course got Openstage IP phones working OK but this is giving me a sore head. I build the extension as a sip client & it does register OK according to the hg1500 logs. I can ring it from a system phone & it does ring but no voice paths. I cannot ring a system phone from the sip extension it just times out.I have all ports open on the network but am even having problems getting an Xlite soft phone working on it from my laptop. The Siemens how to guide makes it look simple but I am really stuggling here. New switch on latest release UK based.