I have an Artisan KA about 9 years old. It has done well but over the last few months the speed control lever has started to jump out of the off position so that when you switch the power on at the mains it starts from speed one. I’ve taken the back off, and the adjustment screw wasn’t all the way in - but if I screw that in then it forces the main contacts apart until the lever moves to position 3. It feels like the lever needs more upward pressure, so that the raised bump on top of the lever is pushed more firmly into the grooves carved into the side of the body (they are hidden under the thin aluminium strip that wraps round the machine). Anyone got any ideas? Many thanks!