Random Hard Limit Prot

I have a laser with a Ruida 633xg controller. I am getting the Hard Limit Prot random error when trying to run a job.

This happened at random positions on the bed. I can run the same job twice and the error will occur at different positions. Bed is 1300 x 900 and the error can trigger anywhere on the bed.

Tested so far
Limit switch diagnosis - nothing showing on the panel as activated - Is there a way of watching the limit switches on the panel during cutting ?
Changed X limit switch - No change
Watched Limit switches during cutting - no activation at the point at which the error occurs.

Looking for suggestions - Software / Hardware ?

it sounds a bit like a broken cable

Is there an order that you would look at them?

It is always difficult to find a faulty cable. If the end stop itself is changed without result, I will replace the cables from the end stop to the controller with new cables. You can also pull an extra set of cables provisionally and see if that solves the problem but in the end it is the same work it takes.