To change the default outbound phone number, go to Settings -> Profile.Click Outbound default.Select the number that you want to be the default outbound number.You can change the outbound number manually before making a call by simply pressing the ">" and then selecting the number from the list. Note that each agent must set their own default phone number.Select the default phone number for your profile from the drop-down list under Default.You can also select a default number for your organization. Find out how, here.