Hello we just got a complain that incoming calls get static

we have a cucm 6.1.2 cluster of 2 servers and 2811 with a pri locally to remote locations

one of this locations is complaining about static and dropped calls

i was checking the controller of the pri and this is what i saw

otal Data (last 24 hours)
     0 Line Code Violations, 561 Path Code Violations,
     0 Slip Secs, 0 Fr Loss Secs, 0 Line Err Secs, 120 Degraded Mins,
     144 Errored Secs, 69 Bursty Err Secs, 0 Severely Err Secs, 0 Unavail Secs

No slips but a couple of errored seconds

also i have the

network-clock-participate wic 2
network-clock-select 1 T1 0/2/0

configured

clocking looks good

Network Clock Configuration
  ---------------------------
  Priority      Clock Source    Clock State     Clock Type

     1          T1 0/2/0        GOOD            T1         
    10          Backplane       GOOD            PLL       

  Current Primary Clock Source
  ---------------------------
  Priority      Clock Source    Clock State     Clock Type

     1          T1 0/2/0        GOOD            T1     

the router is properly grounded

our PRI carrier is Verizon

do you have an idea of what is causing the problem?