Stoves 61GDO

We purchased this oven in March 2007, and thought it looked really stylish.
We decided to buy from a well established family run local oven specialist and were confident of really good purchasing advice - wrong!
The first thing I noticed about the oven was that the knobs became boiling hot when the oven was in use.
Unfortunately I only found out after touching them!
Over time the stainless steel foil has literally melted off them and they now look a real mess.
Having a toddler at the time, we had to install a stair gate across the kitchen door to prevent any accidents.
Within 2 years the main oven had developed a constant 'clicking' noise from the electronic ignition, which I note from other reviews is a common issue.
It is still is a cause of constant frurstration, which unfortunately we cannot afford to get fixed.
I fished out the paperwork today and noticed that the parts are under warranty for 5 years from the purchase date, so I decided to telephone Stoves and complain and try to get replacement knobs.
I was informed that I could get replacement knobs, but an engineer would have to fit them and the call out charge was £142!
After a heated discussion, I was put through to the parts dept. and informed that I could purchase the knobs for £12.51 each, but at the moment they were running a special offer,and I could purchase new knobs for £20.95 including VAT and delivery.
I was then informed that the knobs were re-designed in 2010 - I wonder why?
I am now looking forward to receiving my new set of knobs!
If anyone out there knows how to fix the 'click' themselves, please could they let me know?