Just as a heads up, you may run into a problem: that the jbl does not sense (or ?something) that new/recharged batteries have been put in to the device
the "universal" fix for me has been to connect the device to the pc via the usb cord (fixes frozen screens etc)
it even powers the device on with no batteries in, the bad thing that has happened to me is, i am on my third sequence of replacing batteries (free ones, recharged set 1, recharged set 2) and I've had to hook the device to the pc so it starts every time
otherwise the jbl won't start
other mentions of battery problems
https://www.mobileread.com/forums/showthread.php?t=85199
http://www.mobileread.mobi/forums/sh...t=71101&page=5