This is a SIP trunking install. The SIP provider uses SRV DNS name for their SIP Servers, the SRV record resolves to two A records which point to the actual IP addresses of SIP servers. In theory the Trixbox should use the primary A record resolved from SRV and keep using it unless it fails, but instead the Trixbox uses both A records alternatively every minute or so. When in verbose mode, it shows Trixbox toggles it’s SRV mapping to one or the other A record every minute.
freepbx is a component of trixbox. Try asking at www.trixbox.org.
But so that you know DNS server uses a round robin approach when more then one value is defined for a given value. It’s how the DNS servers hand out the addresses (It is part of the spec which I can’t find the specific document to point you at currently).
You can see this by doing the following:
dig www.google.com
note that you will get more then one result. if you make repeated queries it will rotate the list.