Could you describe the noise? Like, is it a loud "hissing" sound? Or maybe a wind blowing type sound? Or????? Also are the flames in your ceramic logs appearing a little high or aggressive? And lastly, is the noise loud enough to be heard from clear across the room?
tHE NOISE IS HISSING./ IT CAN BEHEARD ACROSS THE ROOM WHEN THE LOGS ARE TURNED UP.
You have potentially one of two (or maybe both) problems. One being the orifices the gas comes out of have become partially clogged and the gas coming out makes the hissing noise. Sort of like trying to make the "SSSSSSSSS" sound with your mouth wide open. Can't be done. You can deal with this yourself by removing the logs and cleaning the holes in the gas pipe. A steel wire brush or something similar will work. However, you will create soot debris that will definitely clog the holes. There a vacuum with a hose and proper end attachment must be used when through cleaning. The other possibility is the gas regulator, that controls the volume of gas, is putting out too much gas. If you are familiar with this assembly and know how to "back it off" so less gas comes out it might very well stop the hissing noise. In fact this part may need to be replaced. Codes require that dealing with gas connections must be done by licensed professionals like plumbers or certified technicians at fireplace stores. So, of course try the cleaning approach first. If no luck you made need to call in a proper "fix it guy."