Gigaset T300/T500 settings
In the Gigaset PBX go to "Configuration" - "Lines" - "Lines" and click on: New Line
Give the Line an unique name, select the provider sipcall pro (CH) in the pull-down list, insert the Registration user name and Password.
Number Area settings:
Just add the telephone numbers for this SIP trunk. The Country Code and Area Code can be filled in, if different than the default setting.
No changes are needed.
Setup instructions in German