My waterbox 20 cube pump has something wrong with it. It has gotten very loud, but unplugging it temporarily fixes the issue. I've already cleaned it and the back chamber but that isn't working. I unplug it and plug it back in and it's quiet, but it gets loud again after anywhere from a few minutes to a few hours. Can someone please help? I'm leaving town for Thanksgiving in a few days and I don't want to return to a broken pump and a dead tank, and I don't think my pet sitter would notice anything is wrong.