How does weighted round robin work?

[bfeole]

Hello,

I have weighted round-robin set to 100% weight on wan2, and wan1 has 0%. However, some traffic still goes out over wan1. The issue is that we have a voice system and the ip that the phones are registered on has to be the same wan ip that it uses to connect back out on the internet, otherwise the person outside their network can't hear the person on the call. Also I have a data vlan and a voice vlan. Currently only the data is going out over wan2 and wan1. voice is just going out over wan2 which is the same wan interface that it's registered with its voip pbx, so that's good. I would like to still understand why wan1 is in use at all, as there's plenty of available bandwidth on wan2. It's probably normal and I just don't understand correctly how round robin works.  Currently I have data limited to 95M so voip will always have 5M to play around with on wan2 and it'll  never need to go to wan1. I assume if data hits 95M it'll then go over to wan1 entirely until there is bandwidth available on wan1. Or maybe there's a better way to do this. I'm open to suggestions.

Thanks,

Me