Incorrect SNMP Interface graphs. Opmanager 12.3

Incorrect SNMP Interface graphs. Opmanager 12.3

I'm having problems with the accuracy of the Interface Graphs since upgrading to 12.3.
The Total Bytes Transferred, Interface Traffic, and Packets are all wrong.
The only graph that is correct is the Interface utulisation.
The interface is a 1Gbps link but connected to a 20Mbps MPLS. The Interface speed in OpManger has been set to 20Mbps.
When the interface was still set to its native speed (1Gbps) the graphs were all incorrect.
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