Spanning-tree bouncing between PVST and PVRST on a single VLAN

I am having an issue on a ring I am working on. Topology is ASR9K -> 4900 -> 4500 -/- 4500 -> 4900 -> back to ASR9K on separate Ten Gig port. Currently I have the link between the 2 4500's shutdown.

All of the switches are running PVRST and the ASR9K is running MST. (Converting the ASR to PVRST next week)

My issue is with 1 single VLAN. I found a switch that hangs off of one of the 4900's was running PVST. I set it to rapid and now instead of showing P2P (Peer), it bounces between Peer and P2P about every 5 seconds on Po7. The same behavior is present on the other 4900 as well but all the switches off of there are also running PVRST. Po7 on this switch is the bundle-e back to the ASR.

4900#sho spanning-tree vlan 69 VLAN0069 Spanning tree enabled protocol rstp Root ID Priority 8261 Address 78ba.f96c.bef6 Cost 1 Port 1287 (Port-channel7) Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec Bridge ID Priority 24645 (priority 24576 sys-id-ext 69) Address a493.4c23.aec0 Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec Aging Time 300 sec Interface Role Sts Cost Prio.Nbr Type ------------------- ---- --- --------- -------- Te1/8 Desg FWD 2 128.8 P2p Po1 Desg FWD 3 128.1281 P2p Po3 Desg FWD 3 128.1283 P2p Po7 Root FWD 1 128.1287 P2p Peer(STP) --------------------------------------------------- spanning-tree mode rapid-pvst no spanning-tree etherchannel guard misconfig spanning-tree extend system-id