Has anybody else had this problem with their GVIF unit? Fitted one about 6 months ago complete with the number plate light reversing camera.

When it works it's great, but about 20% of the time when I go into reverse instead of displaying the rear view, it show a blank screen. Supplier has been great & replaced the unit 3 times, but still have the same issue!

Tried every combination of the dip switches, unit is definitely getting 12V from the reversing light as it switches inputs & believe it must be a problem with the unit (rather than the camera) because the helper reversing lines are not displayed either.

It's driving me crazy