CCR1016 2G Trafic going down

I see almost all of my friends with this problem but i can’t find anything about it on forum. Someone here have this problem too ? The throughput appear that just goes down for a second and return. In Interfaces show for example: 50MBs but it goes down to 20MBs and return to 50MB very fast.

Sorry for bad english.
trafic.jpg