Thanks Eric. Unfortunately the Ethernet switch I am using does not allow me to block Multicast traffic on specific ports. Putting the two Roku's pulling Multicast streams from the NAX on a separate VLAN would be relatively easy to do with the existing hardware.
1, 2, and 3 are all on different Rokus at different job sites. The ones with slow loading time are not pulling streams from the NAX.
For issue 3 Maybe try blocking all multicast to the network port of the Roku's. I wonder if it will also fix the issue with 2.
