Core Issue
The issue is specific to NM-HDV2-1T1/E1 modules used with CAB-E1-RJ45BNC cables. The same configuration with a CAB-E1-RJ45BNC cable works fine when used with NH-HDV module with an E1 controller.
Resolution
This issue relates to a jumper setting on the NM-HDV2-2T1/E1 card. There is a jumper on the NM-HDV2 module that is for Loop power support and can cause issues if it is set to the right-side two pins. The jumper is under the VWIC Slot for each RJ45 connector and must be on the left-side two pins.
Refer to the Configuring E1 Ports for Normal or Wetting Current Mode section of Connecting Voice Network Modules for more details.
Once the jumper is set correctly, the issue is resolved.