I too have a GXP2200 and would like true CTI rather than MakeCall.
I can't remember where I read about this, but I believe the problem is caused by the 2 step process needed for GXP2200 to initiate a CTI call which are documented here:
http://www.grandstream.com/products/gxp_series/gxp2200/documents/gxp2200_gmi_web_service_guide.pdf
The steps given in this document are:
1) User authorisation, e.g.:
http://192.168.1.165/manager?action=login&username=admin&secret=admin&format=json&jsoncallback=?
If successful the authorisation remains active for 15 minutes.
2) Initate call:
http://192.168.1.165/manager?action...an=0&headerstring=&format=json&jsoncallback=?
If I put these URL's into a browser one after the other then the phone will make a call just like the CTI mode should do.
The CTI template for the other Grandstream phones held in C:\ProgramData\3CX\Data\Http\Interface\MyPhone\cti_template.xml looks very different to the above:
http://%%desktopphone_ipaddress%%/c...rd%%&keys=SPEAKER:%%dialled_number%%:SEND
So I think the GXP2200 is definitely a special case phone!
I have been playing around with the template to see if I can implement the above initiate call string, but at the moment I am puzzled since Wireshark only ever shows the MakeCall request coming through to the phone, certainly nothing resembling what I expect the CTI call initiation string should look like (even though the 3CXphone V12 is all set up for CTI).
I'm open to any suggestions on this!!!
Chris