hello, welcome to just answer. my name is XXXXX XXXXX and i will be happy to assist you with your problem. This noise is caused by the gas pressure going through the regulator. It is a somewhat common issue. The easiest and cheapest way that i have found to fix this problem is to add a second regulator just in front of the one on the oven now. You can call an appliance parts dealer and just order a regulator that has a half inch inlet and outlet. they carry cheap ones. also if you have a local appliance dealer in your home area you can go there and ask them to get you a used one. just remove the gas line and install the new regulator and reinstall the gas line.
Your saying the regulator is bad?
can it come off the old stove I replaced it with?
no it is not bad. for some reason certain pressures on some regulators causes this. we see it on brand new units. you should be able to use the one off the old unit.
as long as you can get the fittings to connect them.