480 Channels/devices

Make sure that the K96 wall connector is wired correctly.  K96 connectors are often pinned differently than Ultimate.
K96 wall plates should be pinned:
  Shield goes to pin 1
  Data (black)  pin 2
  Data (red)     pin 3

The DMXUltimate converter sends an 1-1 patch at console power-up.
Replace old ni-cad batteries on the K96 cards.  These hold the rack's softpatch and can be problematic if they are old.