SautiKit's registrar is SIP over UDP, which browsers cannot speak, so headset calling runs through a desktop softphone (MicroSIP on Windows, Linphone or Zoiper anywhere). Register it with these settings and you can talk and listen directly.
Put the domain in without the port and set the outbound proxy separately — a port typed into the domain field is usually ignored and 5060 tried instead, which will not connect.
Ring … from any phone.
You should hear a welcome message, then a menu: 1 connect to a consultant, 2 leave a recorded message, 3 hang up. Every step appears in the feed.