Can I change default outgroup prefix '9' to another one, for example '8'?

Yes, we can configure our virtual SIP PBX to fit this requirement. Of course, please sign into your account firstly.

Please click menu "Data / system / Basic". In the configuration page, please change "outgroup call prefix" to '8', then click button "update" to save your modification.

outgroup call prefix = 8

Then, when we dial "8xxxx", calls will be sent to outside through external line and outgroup-prefix '8' will be deleted finally before the called parties "xxxx" receive calls.