If you want to activate the outbound ringtone for your calls, you need to go to the “Settings” - “Account” – Tick the box which says “Enable ringtone in dialer” and enjoy calling from Adversus.
Do not forget to "Update client settings" at the bottom.
P.S. If you don't hear the calling indicator before the customer picks up the phone, don't be surprised. That means that your outbound ringtone is not enabled.