Product review (5 stars): Great product, but remove the shipping bolts!!!
Take the shipping bolts out!!!!  I almost launched this through the drywall into the bedroom when I started it up...I thought it was possessed and was going to try to ship it back until I carefully read every word in the manual.  They should put a warning sticker on the power cord or the front window warning you to do that.  Once I realized it's not supposed to sound like that, I removed the shipping bolts which they put in to protect it in transit, it has worked perfectly.  I ordered it online to replace one just like it damaged Ina lightning storm, so it just showed up on the porch, whereas the original was put in place by professional installers.