I am having trouble charging from my Brunton solar charger and also an external battery. My other phone charges from them without any issues, did casio put something into the phone to prevent me from connecting to them? Both connect by USB and it does recognize that it is plugged in but does not do anything while plugged in. I have the USB connection set to charge only and still nada. Any suggestions? The whole point of buying this rugged phone was to take it with me on a Thru Hike of the Appalachian Trail... all 2200 miles of it. I would hate to have leave this one behind because of a lack of solar charging ability.