The default sound settings will not works.
In my case, Sound Out and Ringing works with pulse, but Sound In need to set as hardware device. Set Sound Out and Ringing fast, testing with "make a test sound". When it working, set Sound in and use "make a test call".
When tehe setting is complete, click on "apply" to save settings.

The my example:
Click on [S] icon (Main Memu)
Options->Sound Device
Sound In: MVidia CK804 (hw:CK804,0)
Sound Out: pulse
Ringing: pulse

