I going to tell you whatīs my issue about, I press start, it starts ok but at some points energy drops down just minimally, if I put the hand on the plattern at some points it will stop completely if I push it a little bit it will continue.

I had a look throw internet and some people said to me change this change that.
I have changed transistors Q2 and Q3, chip an6682, I have check condensor c1 and itīs correct.

how dou you fix this issue?