Silver Cross Pioneer - Front Wheels Buckle - Does anyone have the same issue?

I am having issues with Silver Cross accepting there is a design fault with their Silver Cross Pioneer. The product is marketed as an 'all-terrain', however the front wheels struggle coping with basic terrain - they buckle/jam when going over any type of object, whether small or large.

On one occasion the pram flipped over and landed upside down! My daughter hit her face of the concrete!

Has anyone experienced the front wheels buckling/jamming? Or in the extreme case flipping over?