My Mikrotik CCR 1009 router os version is 6.39.2


I am having some problem in my mikrotik , The problem is i am using this mirkotik as NAS but
since todays morning there is fluctuating the TX and RX traffic of WAN interface and LAN interface as well .
But at the same time thre is no traffic fluctuation in Fp Tx and FP Rx,and also there is no problem with
browsing and others and this does not effects any problem in network for users but the bandwidth is fluctuating
continuously in my WAN and LAN interface as well ..And my CPU utilization is little bit high and it goes upto 20%
and having 2 GB RAM .



What can be the problem of this issues ??
Is there any problem with the Ports