I'm trying to get multicast setup on a 2960XR to support a Cisco Mobility Express deployment but I'm having issues w/ devices seeing each other as expected. I initially suspected it was on the wireless side, but I was able to take an access point from another site (standard autonomous ap) that was working fine at the other location and connect it to the 2960XR and had the same issues. The 2960XR is L3 and acting as the default gateway for any device in the building.
Switch has the SVI for vlan 100 and that vlan is configured w/ this:
int vlan 100
ip pim sparse-dense-mode
ip pim rp-address 192.168.100.1
The access points are in vlan 100. For testing I moved the clients to vlan 100 as well but that seemingly make a difference.