[akvadrako]

It's tolerance. I've bought several of the quietest fridges and they all bother me. Old fridges sound nicer but newer ones are actually quieter.

[esseph]

Is it the fridge noise in particular or all noises that you find you are sensitive to?

[akvadrako]

In practice the fridge is the only common thing. Most stuff in a house is quiet or, like fans or furnaces, make simple sounds that are easy to ignore.