Just installed a Harmon XXV in our home. Haved burned about two bags of pellets and have a squelling noise coming from the stove. Any suggestions on how to fix it? The dealer is going to charge $40 to come out but can't come for another week. Is there anything that can be lubricated? The squell will wake a sleeping person. Is there anything that I can do myself to stop this or is it an issue that must involve a technician? Thanks for any help.