I've had my feeder up for over 2 months, and have a variety of birds come to feed. I have sunflower hearts and niger seeds, hoping to attract goldfinches. Behold, 2 months later they have (I think) set up nest in my neighbour's garden, out of sight for me but they fly past my garden hundreds of times every day. They come down for a drink at my water bath in the morning and evenings, and they've perched on the feeding station but they've never eaten anything. The sunflower hearts are fresh and very popular, can anyone tell me what is going on and how I can get them to come and eat?