Crossover valve popping

[terryboxman]

Our Burstner crossover gas valve stated to “pop” a while ago. It now happens almost every day. Is it the crossover valve that’s popping or the gas regulator that’s directly underneath it? And what can we do about it?

 

[Lenny HB]

What do you mean by popping?
Is it an auto changeover valve and if so what type, if you post a photo it would help.