When I ping the IP address of IP Phone, there is 20% packet drop but the voice call is normal. Is it a normal situation?

How to change the path of MPLS core from one PE to the other PE with redundancy link? The IGP is OSPF and running MBGP among PE routers.

How to make trace and ping are available in MPLS PE router? Can I ping or trace a customer IP from the PE router?

We have a MPLS VPN network with 7206VXR as the PE switch. The 7206VXR has Ethernet Port for connecting to our switch for VoIP. I want to confirm whether can I enable QoS on the Ethernet or not for VoIP?