What is the TTL set for on the multicast source? If it's too low, it won't work. If you can't see or set it on the multicast source, then do a packet capture at the PIM RP and see what it's set to.
Run into this issue more than once.
Perfect, glad I could help...just update the status of the thread to 'Solved'Many many thanks for your great help and idea! It did exactly what I wanted!
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