Mine just fired up in the case.
It just started, luckily I was sitting right by it and heard that oh-so-familiar sizzle. Opened the case and touched the cone, and it was very warm.
I hadn't even had it charging for long, maybe five mins? It was still lit up and charging when it started sizzling, so if I hadn't been right here, I wouldn't have even noticed it.
I pulled it out, let it cool down, hit it (worked fine), and put it back in the case. Now it's charging fine. How many is tht now? Three? I forget how many others have had this issue.