Ink overflowing from LK cassette and leaking

Newly purchased 7900 with new cartridges with Neutral K7 inks. After initial fill (after flushing), good nozzle check; and one print; ink ran down front right leg of stand and quickly filled a new maintenance tank. It drained 150+ml from LK cassette with no apparent leak around cartridge, no spill around docking station or in case around print head. Does anyone have any ideas. Jon suggested changing the LK cartridge which I am waiting on. Any other thoughts?

I suggest the same thing. We sent the LK out so it will be with you very soon.