QOS drops without any congestion?

Hi,

I do have this issue that the drop continuously increasing? Please see the below configuration. Any idea? Is this due to bursty traffic and or is this normal?

GigabitEthernet0/1

  30 second output rate 6676000 bits/sec, 2260 packets/sec

policy-map int-queuing

class class-default

  service-policy queuing

  shape average 180 mbps 16000 bytes

policy-map queuing

class gold

  priority level 1

!

class control

  bandwidth remaining percent 10

!

class s1

  bandwidth remaining percent 25

  queue-limit 900 ms

!

class s2

  bandwidth remaining percent 25

  queue-limit 900 ms

!

class s3

  bandwidth remaining percent 30

  queue-limit 2000 ms

!

class class-default

  bandwidth remaining percent 10

  random-detect default

Policy queuing Class class-default

      Classification statistics          (packets/bytes)     (rate - kbps)

        Matched             :         33879336561/17327068811503       4371

        Transmitted         :         33713647964/17167375847937       4419

        Total Dropped       :           165693561/159796685571         0

      Queueing statistics

        Queue ID                             : 131438

        High watermark                       : N/A

        Inst-queue-len  (packets)            : 0

        Avg-queue-len                        : N/A

        Taildropped(packets/bytes)           : 0/0

        Queue(conform)      :         33713647964/17167375847937       4419

        Queue(exceed)       :                   0/0                    0

        RED random drops(packets/bytes)      : 165693561/159796685571

        WRED profile for Default WRED Curve

        RED Transmitted (packets/bytes)            : N/A

        RED random drops(packets/bytes)            : 165693561/159796685571

        RED maxthreshold drops(packets/bytes)      : N/A

        RED ecn marked & transmitted(packets/bytes): N/A

Thanks