Hi jandafields,
Thanks for your advice. However to my knowledge the beta of 5.8 is only standard package. I use NTP and Multicast as well. So I have to stick to the official releases. 
Anyhow last night I found out what the problem was.
The issue was that the bridge interfaces needed to have ARP enabled. I was using Reply-Only and for some to me unknown reason it would not create a local-link without ARP enabled.
After enabling ARP on the bridge interface it took 10-15sec before it created the link interfaces. 
I never looked at this when the issue occurred since I was under the impression that ARP was no longer needed.
From what I have reed on the matter ARP was replaced by NDP.
Does anyone know why this is required?