Five flavors of Dumb

I read this a couple of years ago now, but I distinctly remember reading this book, really enjoying it, and then it just...cuts off. Whole subplots (or, really, one in particular) are completely dropped. It was so jarring that I ended up mad at the entire book. Mad at the parents, mad at Piper, mad at the band. I really needed a conclusion here.

Am I just remembering wrong? I may need to pick this one up again.

Nothing too spectacular but I did enjoy it. Thought the ending was a bit abrupt, though. It felt like the whole book was about this band of characters–characters outside the band as well–and their major flaws. The content of the book was basically exploiting the flaws and then just reading about they're fixed.

I really did enjoy this book. I loved the idea behind it. A deaf girl, managing a band? What can go wrong?