> Some also add incredibly annoying high pitch whines. That seemingly nobody seems to notice but me. That drove me crazy for about a week trying to figure out

> Some also add incredibly annoying high pitch whines. That seemingly nobody seems to notice but me. That drove me crazy for about a week trying to figure out what the noise was coming from... Pinhole water pipe leak? Cat stuck in the flue? Once I realized what it was, I didn't mind it much. It is better than loud old compressors suddenly kicking on and burrr'ing away then stopping.