What happens when you bypass pix-a and source the ping from the switch itself? Send a regular ping first and then an extended ping but sourced from another interface (other than the vlan/routed egress interface). This test will force a sw lookup in o...

It is probably due to IGMP snooping where mcast traffic is constrained. Try disabling it on the vlan. If still busted, check the multicast group you are using and assure it is not in the reserved range.RH

The first hop router where you execute show ip route x.x.x.x should show the next-hop for the subnet and not the exact host (unless you specfied it otherwise). The sup should use the same hop unless it is running a routing protocol where you have dua...