Why is there a noise and big flame when starting my gas cooker? I installed a new gas bottle a few days ago for my stove and trying to find out why the following is happening.

When the gas hasn't been used for a few hours, the moment you turn the gas button on the stove there is what looks like a higher pressure wave that comes with a large flame and a 'wooof' sound when the gas ignites.

The the stove works normally. It takes 3-4 hours of not using it for this to occur again.

It looks like there is a pressure buildup in the gas line when it's not in use.

What could be the reason?



Here is a video: https://imgur.com/a/WTiI4id

If you want sound for a full experience: https://we.tl/p9CR4Dihok :)
This sounds like delayed ignition where a greater than normal amount of gas is present when the burner gets spark.  If you manually initiate the spark independent of turning on the gas you might try starting the spark first and then turning on the gas.  Also the spark ignitor may be slightly out of place, moved during cleaning, etc.  There are all sorts of stoves.  A photo of the controls, burner and ignitor would help.  You could also check the manual.  

After viewing/hearing the video it seems to me the ignition is rather forceful.  This might point to the regulator and too high gas pressure.  A technician could test the gas pressure after the regulator.