In-Home streaming disable IPv6, force only IPv4?

[lozt.again]

I used to be able to use Steam In-Home Streaming using OpenVPN and a UDP broadcast relay program over the internet with my pfsense firewall.

Recently this stopped.

I checked and can see that from wiresharks there are only IPv6 packets coming from my PC for the service, and not IPv4 broadcasts.

Does anyone know how I can get it to only work with IPv4?

And an even longer shot, has anyone any knowledge on how to get that IPv6 traffic relayed? (I'm presuming it is either link-local, or multicast)

EDIT: Just FY, it doesn't matter if you disable IPv6 on the interface, as if I do so, it just never sends out the IPv4 broadcast.