Please help if so! I've just moved into a new house with this microwave and I can't get it to heat things! I don't have the heating rod which apparently it needs for liquids. Should I get one? I also heated some cheese and it didn't melt, so I don't think that's the issue. I put it on the setting shown in the picture and I have tried different wattages but although it lights up, makes noise and works on the oven setting, the microwave won't work. Am I being stupid or is the microwave broken?