I have purchased several ingenuiTea's over the last few years. I use them everyday and have given Many away to friends because I love them so much. After a while of use I generally need a new one. I purchased a new 32 oz and am having the same problems that you describe! I am also dissapointed that when I pour boiling water into the tea pot the filter floats up and many of the tea leaves float down Under the filter!! I too do not like how they have changed the design!!
I ordered my first ingenuiTEA and had the problem with the floating filter. But I don't think it was the ingenuiTEA, I think it was the filter itself. Adagio sent me a replacement filter and it now works great! It snapped into place and hasn't moved at all. I use my ingenuiTEA once or twice a day, heat the water directly in it and everything.