Discards on Cisco Switches

I am receiving discards and CRC errors on some interfaces in a port group

First off, the Gi1/ interfaces

LKS-CORE-002#sho interfaces counters errors

Port       CrcAlign-Err Dropped-Bad-Pkts Collisions   Symbol-Err
Gi1/1          28747235                0          0   2169382389
Gi1/2                 0                0          0            0
Gi2/1                 0                0          0       629850
Gi2/2                 0                0          0       670140
Gi2/3                 0                0          0       732870
Gi2/4                 0                0          0       620925
Gi2/5                 0                0          0      1273215
Gi2/6                 0                0          0       748935
Gi3/1                 0                0          0            0
Gi3/2                 0                0          0            0
Gi3/3                 0                0          0            0
...
Po1            28747262                0          0   2169382839

#The Port Group

interface Port-channel1
 switchport
 switchport trunk encapsulation dot1q
 switchport mode dynamic desirable
 qos vlan-based
 qos trust cos
!

#The interfaces on LKS-CORE-002

interface GigabitEthernet1/1
 description ** Connected to LKS-CORE-001  Gig 1/1 **
 switchport trunk encapsulation dot1q
 switchport mode dynamic desirable
 service-policy output autoqos-voip-policy
 qos trust cos
 auto qos voip trust
 tx-queue 3
   bandwidth percent 33
   priority high
   shape percent 33
 channel-group 1 mode on
!
interface GigabitEthernet1/2
 description ** Connected to LKS-CORE-001 Gig 1/2 **
 switchport trunk encapsulation dot1q
 switchport mode dynamic desirable
 service-policy output autoqos-voip-policy
 qos trust cos
 auto qos voip trust
 tx-queue 3
   bandwidth percent 33
   priority high
   shape percent 33
 channel-group 1 mode on

-------- The Other Core -------
LKS-CORE-001#sho interfaces counters errors

Port       CrcAlign-Err Dropped-Bad-Pkts Collisions   Symbol-Err
Gi1/1                 0                0          0         1530
Gi1/2                 0                0          0         1530
Gi2/1                 0                0          0       630105
Gi2/2                 0                0          0       648210
Gi2/3                 0                0          0       743325
Gi2/4                 0                0          0       965685
Gi2/5                 0                0          0      1230375
.....
Po1                   0                0          0         3060

#The Port Group

interface Port-channel1
 switchport
 switchport trunk encapsulation dot1q
 switchport mode dynamic desirable
 qos vlan-based
 qos trust cos
!

#The Interfaces on LKS-CORE-001

interface Port-channel1
 switchport
 switchport trunk encapsulation dot1q
 switchport mode dynamic desirable
 qos vlan-based
 qos trust cos
!
interface GigabitEthernet1/2
 description ** Connected to LKS-CORE-002 Gig 1/2 **
 switchport trunk encapsulation dot1q
 switchport mode dynamic desirable
 service-policy output autoqos-voip-policy
 qos trust cos
 auto qos voip trust
 tx-queue 3
   bandwidth percent 33
   priority high
   shape percent 33
 channel-group 1 mode on
!

These are fibre connections between the two core switches. If this was copper I would check the speed/duplex etc to be 1000/full and force the speed on all ports. I am not sure what I am supposed to do with fibre connections?

Secondly the Gi2/ interfaces - also Fibre, these are going to the user switches

#LKS-CORE-002
interface GigabitEthernet2/1
 description Uplink to LKS-T2S1-SW3-013
 switchport trunk encapsulation dot1q
 switchport mode dynamic desirable
 service-policy output autoqos-voip-policy
 qos trust cos
 auto qos voip trust
 tx-queue 3
   bandwidth percent 33
   priority high
   shape percent 33
!
interface GigabitEthernet2/2
 description Uplink to LKS-T2S2-SW6-016
 switchport trunk encapsulation dot1q
 switchport mode dynamic desirable
 service-policy output autoqos-voip-policy
 qos trust cos
 auto qos voip trust
 tx-queue 3
   bandwidth percent 33
   priority high
   shape percent 33
!
interface GigabitEthernet2/3
 description Uplink to LKS-KINGS-SW3-019
 switchport trunk encapsulation dot1q
 switchport mode dynamic desirable
 service-policy output autoqos-voip-policy
 qos trust cos
 auto qos voip trust
 tx-queue 3
   bandwidth percent 33
   priority high
   shape percent 33
!
interface GigabitEthernet2/4
 description Uplink to LKS-T3S1-SW9-022
 switchport trunk encapsulation dot1q
 switchport mode dynamic desirable
 service-policy output autoqos-voip-policy
 qos trust cos
 auto qos voip trust
 tx-queue 3
   bandwidth percent 33
   priority high
   shape percent 33
!

and so on....

#LKS-CORE-001
interface GigabitEthernet2/1
 description Uplink to LKS-T2S2-SW1-011
 switchport trunk encapsulation dot1q
 switchport mode dynamic desirable
 service-policy output autoqos-voip-policy
 qos trust cos
 auto qos voip trust
 tx-queue 3
   bandwidth percent 33
   priority high
   shape percent 33
!
interface GigabitEthernet2/2
 description Uplink to LKS-T2S2-SW4-014
 switchport trunk encapsulation dot1q
 switchport mode dynamic desirable
 service-policy output autoqos-voip-policy
 qos trust cos
 auto qos voip trust
 tx-queue 3
   bandwidth percent 33
   priority high
   shape percent 33
!
interface GigabitEthernet2/3
 description Uplink to LKS-KINGS-SW1-017
 switchport trunk encapsulation dot1q
 switchport mode dynamic desirable
 service-policy output autoqos-voip-policy
 qos trust cos
 auto qos voip trust
 tx-queue 3
   bandwidth percent 33
   priority high
   shape percent 33
!
interface GigabitEthernet2/4
 description Uplink to LKS-T3S1-SW7-020
 switchport trunk encapsulation dot1q
 switchport mode dynamic desirable
 service-policy output autoqos-voip-policy
 qos trust cos
 auto qos voip trust
 tx-queue 3
   bandwidth percent 33
   priority high
   shape percent 33
!
interface GigabitEthernet2/5
 description Uplink to LKS-T3S2-SW10-023
 switchport trunk encapsulation dot1q
 switchport mode dynamic desirable
 service-policy output autoqos-voip-policy
 qos trust cos
 auto qos voip trust
 tx-queue 3
   bandwidth percent 33
   priority high
   shape percent 33
!
and so on....

So, in summary I am experiencing discards on my fibre uplink ports between the user switches and the interconnect between the two core switches

help please :)