Hi Garry,
With the setup I deployed last year I don't believe I saw a round robin behaviour. However, with my config the second SIP trunk was via a seperate SE server (backup pool) which is the equivalent of a different pool. I think this would mean that trunk is only used if the primary pool route was down, hence no round robin for this configuration.
I'm sure the link you provided is accurate, so if you have two SIP trunks in the same pool providing access to the same destinations, then you would get round robin.
Jed
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