I live in Columbus, Ohio. On windy days we get a howling noise from our glass block window, mostly in the winter, I cannot fell any air coming in. Our house is 5 years and this has been going on since we moved in. We've had the builder, window mfg. and siding co. out. Each has been here more than once. They've renailed the window several times, but to no avail. I even dumped an entire tube of caulk around the window and that did not help. Last winter 3 more windows began making the same howling noise. These are single hung windows. All of the window face the south. Any ideas how to fix?