I am trying to build exactly this with help from another post: (SIP Doorbell, android tablet and HA integration - #2 by greengolfer)
I am using a Hikvision DS-KB8113-IME1 doorbell and it works great with this custom component and the audio works well too. Thank you AlexxIT! Please note that the previous version of this Hikvision doorbell does not work as a standalone model so is less suitable if you also want to use the SIP functions as part of an intercom system.
I also have Annke C800 IP cameras and haven’t been able to get them to work directly with this component but can use them if I pick up the rtsp stream from Blue Iris instead, does anyone know what might be causing the rtsp stream direct from the cameras not to work? They are streaming in H264 both direct and from Blue Iris.