It was the same in our Autoquest (Dometic RM4230). The Burstner has a RM627iL which has a ticking sound when the gas isn't lit. The rotary switch is held in until the ticking stops, which means the gas is lit. AFAIK if the gas goes out for some reason the ticking will start again.
The more recent models (like the one in your Hymer) have auto-re-ignition so if the gas goes out (unlikely) the system will re-light it. As others have said, when the flame is out, the igniter emits a constant ticking until the flame is re-lit. This works when the flame system is warm - that's why you have to hold in the temperature dial for about 15-20 seconds after the ticking stops when first lighting the gas from cold. Once the burner is hot, the auto-shut-off will stay open to allow the gas to continue flowing.
Normally when lighting manually, you can hear a soft 'pop' when the gas ignites, then the ticking stops and you hold in the temp dial as above. If at any point (when set to gas) you hear ticking, the flame has extinguished (and failed to re-light automatically).
We have a Hymer with Electrolux Fridge and auto-ignition. Often on gas, the fridge will ignite but the auto igniter will keep on ticking away! Sometimes it will stop after a while. It can be fine for ages and then will do it! I've noticed that if I drive a short distance with the fridge lit it stops!! Any ideas? Dave