Hi,
I think the problem is in the 10Giga modules.
Reset the interfaces at both ends and chek the configuration associated with them.
What model of router are you using?
That router has a 10 Giga module also?
Post data: I had a similar problem when we connect two switches 3560 using media converters (utp to fiber). The switch shows in the log flapping messages and dissable the interface.
We reset the media convertes and the problem was resolved.