Boot open alarm - Please Help

I'm new here but at the end of my tether so would really appreciate your help.

I have am 09 Fabia 1.9 estate.

The problem is the boot open warning keeps triggering randomly, with associated bongs while driving and alarm when stationary.

I have read countless threads on this...

There is no evidence of any water ingress or leakage from the wash wipe.

I have fitted a new boot lock.

I have disconnected the lock from the wiring loom and run the car.

There is no sign of any damage to the loom.

Under all circumstances the problem is the same. Car is fine for a while, either at rest or driving, then boot open light comes on and alarm goes off or the internal bong goes off.

Please help!