The microwave integrated into my Siemens oven (HB86K570B/06) seems to be taking an unusually long amount of time to heat things up. I first noticed it when it took about 4+ minutes to get milk to a point that it steams. Just tested and it takes 3m30s at 900W to boil a glass of 250ml of water. Is that normal and if not, what could be the issue?
