Packet loss inside VPLS, but not out?

We have configured MPLS as per example on Wiki. We have many VPLS setup. They work good, but on occasion (random times) we will see about 5 seconds of completely 100% packet loss inside the VPLS tunnel. Outside the tunnel there is not a single packet dropped. Sometimes the entire VPLS interface will go down and come back up. disable-running-check=yes does make the interface not go down, but we still see the packet loss.
Because it’s almost exactly 5 seconds, it seems like maybe it’s something timing out, not getting a hello, or…? Any ideas? It’s causing us much frustration.

Hi spectrasurf, did you ever find a resolution for this? We are seeing a very similar problem with BGP based VPLS circuits and also routed MPLS. This is resulting in between 0.5 and 1% packet loss on the circuit yet outside between loopbacks there is no packet loss. Any assistance appreciated.