Hey FreeSWITCH Users, Interesting issue here. We're connecting to Nexmo, a major SIP provider. They do load balancing of their SIP servers; a set of four IPs behind sip.nexmo.com. I have a FS sip set up to register to their server. However, in INVITE, it seems to switch IPs. Basically it goes like this: US -> INVITE sip.nexmo.com (IP1) IP1 -> 407 AUTH US -> INVITE sip.nexmo.com (DIFFERENT IP2) nonce and auth stuff IP2 -> 904 FAIL Here's my config: <include> <gateway name="sip.nexmo.com"> <param name="username" value="XXXXX"/> <param name="password" value="YYYYY"/> <param name="from-user" value="XXXXX"/> <param name="from-domain" value="sip.nexmo.com"/> <param name="proxy" value="sip.nexmo.com"/> <param name="expire-seconds" value="600"/> <param name="register" value="true"/> <param name="retry-seconds" value="30"/> <param name="extension" value="5000"/> ... How do we stop this from happening? Setting from-domain and proxy to an IP behind their load balancer fixes it, but that's clearly suboptimal. Why is FS resolving the sip.nexmo.com DNS twice? Thanks!