At the beginning of troubleshooting this issue we had a 2 node cluster:
proxmox01 (pve 3.2-4)
proxmox02 (pve 3.3-1)
The second node had been part of the cluster for 1 week when we migrated 5 containers and 2 VM's to it. It remained functional for over a week. This is when I left the office...