Linux tip for Centos6 - intermittent problems

I was having all sorts of problems with serviio (and miniDLNA also) on my Centos box with a network bridge setup (br0). There was some problem with multicasting that caused the server to be intermittent. It was giant pain.

Anyway - this was the answer:
echo 0 >> /sys/devices/virtual/net/br0/bridge/multicast_snooping

i put this at the end of the /etc/rc.d/rc.local file and all was well.

I'll leave this here just in case someone else is out of ideas. (I checked the firewall, switches, router - it was mess)