troubleshooting Question

Interface Errors on Point to Point T1

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jgoller asked on
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I posted here a week ago about a Point to Point T1 that kept dropping.  Errors were found by the line provider (SBC) finally, and we figured everything was good.  But no, more problems keep popping up.  The lastest problem that I can't figure out is the errors showing up on 4 of the 8 serial interfaces on our 3600 router (these all go to remote sites via T1's).  Only one of them keeps dropping, but the errors increase at a regular rate on all of them.  Today on the smart jack, those 4 cards were flashing a yellow light next to HCRC (I don't know what that is).  It might be that I have a clocking problem, I know the remote sites are set for the line, but we never set anything on the main 3600 router (but half of them work fine without any clock configuration).  My question is how do I set up clocking on a 3600 (version 12 IOS) for each interface, or is that not even my issue?  The following is the sho int from one of the misbehaving lines (the other three are the same except they have Total Output Drops: 0):

DataCenter3600#sho int ser 5/1
Serial5/1 is up, line protocol is up
  Hardware is DSCC4 with integrated T1 CSU/DSU
  Description: Franklin
  Internet address is
  MTU 1500 bytes, BW 1544 Kbit, DLY 20000 usec,
     reliability 255/255, txload 1/255, rxload 1/255
  Encapsulation HDLC, loopback not set
  Keepalive set (10 sec)
  Last input 00:00:00, output 00:00:00, output hang never
  Last clearing of "show interface" counters 05:16:00
  Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 2
  Queueing strategy: weighted fair
  Output queue: 0/1000/64/0 (size/max total/threshold/drops)
     Conversations  0/5/256 (active/max active/max total)
     Reserved Conversations 0/0 (allocated/max allocated)
     Available Bandwidth 1158 kilobits/sec
  5 minute input rate 0 bits/sec, 0 packets/sec
  5 minute output rate 0 bits/sec, 0 packets/sec
     16811 packets input, 1948054 bytes, 0 no buffer
     Received 2103 broadcasts, 0 runts, 0 giants, 0 throttles
     61092 input errors, 1451 CRC, 59641 frame, 0 overrun, 0 ignored, 0 abort
     21681 packets output, 15951761 bytes, 0 underruns
     0 output errors, 0 collisions, 23 interface resets
     0 output buffer failures, 0 output buffers swapped out
     30 carrier transitions
     DCD=up  DSR=up  DTR=up  RTS=up  CTS=up

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