Hi Folks,
Some pointers to start your multicast troubleshooting,
IGMP
show igmp interface detail | no-more
show igmp group detail | no-more
show igmp statistics | no-more
PIM
show pim interface | no-more
show pim neighbors | no-more
show pim statistics | no-more
show pim join extensive | no-more
show pim source detail | no-more
RPF
show multicast usage | no-more
show multicast rpf summary
show multicast rpf | no-more
show multicast route extensive
show route table inet.1 | no-more
show multicast next-hops | no-more
show multicast statistics | no-more