First time back to this forum in a few years, the lack of responses has me concerned, 25 on the first page, 14 have 0 responses. Not sure if it's worth a new post on my issue.

I have a LG LFX25960ST (French Door Refrigerator with Bottom Drawer Freezer) that for a month or two now randomly starts making a loud whirring/humming/vibrating noise. The noise comes from the back of the freezer compartment and stops when the fridge doors are opened, not when the freezer door is opened. It seems like this would be one of the fans (replaced the ice fan about 6 months ago due to an IF error), but oddly just briefly opening the fridge door and reclosing it immediately kills the noise even though the fan kicks back on when you shut the door. I do get ice buildup in the styrofoam lining the back freezer wall (recurring problem) and recently thawed the whole wall and pressed all of the melted water out of it. Is this most likely the second fan in there, the ice buildup due to a faulty defrost sensor or main board, something else completely? Any help is greatly appreciated. Thanks.