We have a Lifesize Icon 800 unit connected to the Lifesize Cloud. We are using SIP registrar 2 to register the Lifesize with our Shoretel system. Incoming calls work fine. You can dial the internal extension or the external DID of the Lifesize with no issues. However, we are unable to make any outgoing calls via the Lifesize phone. All we get is a "Call Failed" message. Has anyone ran into this issue before?