Why is my refrigerator so loud? Can I fix this?
Here's an outside the box idea (which assumes that your main problem is that it wakes you up):

Get one of those timer plugs like they have for holiday lights and let it "unplug" your fridge while you sleep. You'll need a beefy one to handle the compressor spike when it kicks on (check the ratings on the timer plugs and compare it to the max rating of your fridge). Since the fridge door won't be opened, your food should be fine, though I'd test it the first night to be sure with a fridge thermometer. If your fridge is still cold in the morning, you might have a solution!