Window insulation

Hello, Between 7:00 AM and 12:00 PM, with the sunrise, I hear crackling noises coming from the window frame. The sound occurs approximately every 2 minutes and continues for almost 3–4 hours. I believe it is related to expansion and contraction because the noise does not occur on rainy or cold days. There are also bubbles on the wooden part under the window; the noise might be coming from there as well, but I am not completely sure. I live in Spijkenisse. I would appreciate it if a technician in the Rotterdam area could come and inspect the issue free of charge and provide a quote afterward. Identifying the exact source of the problem is very important to me, as I am not sure whether the noise comes from the window frame itself or from the wooden part underneath (which I marked as 1, 2, 3). I tried applying silicone spray to the wooden parts, but it did not help.