This is a design question for the Phone app, not for pulseaudio. The Phone app might choose to, for example, play the ringtone just through headphones for the first two or three seconds, to give you a chance to answer the call without waking up people nearby; and then switch to playing through speaker, in case your headphones aren't in your ears. I'm not saying it should necessarily do that, that's just one possibility.
Unfortunately, the Phone app spec currently doesn't even mention ringing. <https://goo.gl/0hy3A1> The design for ringing should also describe what should happen if other audio is playing when the call arrives. ** Package changed: pulseaudio (Ubuntu) => dialer-app (Ubuntu) -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to dialer-app in Ubuntu. https://bugs.launchpad.net/bugs/1483888 Title: Aquaris E5: Ringtone + buzzer cannot be heard when jack/headphones plugged Status in Canonical System Image: New Status in dialer-app package in Ubuntu: New Bug description: Aquaris E5: Ringtone + buzzer cannot be heard when jack/headphones are plugged. This I consider a bug, since user cannot depend on the such a device with hearing calls / being woken up in the morning. Typical scenario: listening to music/watching movies during the night and falling asleep. It already happened several times to me that I did not get awakened by the phone in the morning, since headphones were plugged into the device and all the sounds could be heard only in headphones. To manage notifications about this bug go to: https://bugs.launchpad.net/canonical-devices-system-image/+bug/1483888/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp