Garage Light Switch Not Working Properly?

I had a BC 10 amp light switch fitted to the safety board in my garage with 2 sets of fluro lights. I thought I was turning the switch on wrong! Initially it would make a buzzing noise and sometimes would turn lights on and other times it wouldn't. Electrician who fitted the switch and lights says its not his wiring, it's the lights. The switch would initially set safety switch off and cut power in the garage, or lights would trip its own switch and turn off? I have spoken to Midis who say it's the switch not the lights! My thought is it is the switch or the way it has been fitted. Any ideas? I am not sure why a normal light switch wasn't wired at the time.