Hi there,
I've been implementing Multicast throughout our network. The network consist of about 400 VLANs, many 4000 Sup II access switches and at the core everything is intervlan routed by a couple of 6500s. The multicast server is on a new 4500 sup V switch. I've implemented PIM dense mode on each vlan in the core, and used a mixture of CGMP and IGMP snooping on the switches, depending on which is supported.
Our multicast streams run fine from VLAN to VLAN, however if more then a couple of ppl join in on the multicast, the stream gets broken up for everyone, it starts to stutter or sometimes connection is simply gone for a minute or so. I've tried connecting my own laptop on the serverswitch directly on the same vlan, no problem, so it's not the server but must be either the routing or switching in between. However none of the trunk, access or serverports along the way have a high utilization, and there is no problem with unicast to the server (ping etc.) I have no idea what's going on...