This topic has not been posted on in a while, but I have a question about my PT. It just stopped working after about a week. When I bought it, it was my understanding that I plug it into my computer USB port, and it would always stay charged. But as I read this thread, it sounds like you have to charge them. Did I read it all wrong? I plugged my PT into a charger, and it indicated that it was fully charged. I'm confused. Maybe the PT just died.