My PS4 controller just died right now while playing on PC. Slow orange blink and then dead. I've been using it on PC with an USB cable (around 150 hours of gameplay spreaded out in a whole 3 years - I prefer keyboard mostly). I guess it's been charging while playing, since I need the USB connection to plug it on the PC. So the posts about the battery makes sense, but it could be a coincidence so it doesn't discard the conductive film option. I don't have a PS4 anymore, and when I plug it directly into a wall plug it doesn't even blink.