[Patrick]

Check how tight the banana plugs fit in the battery, from the esc and from the balancer. Those things always loosen up. Two guys I race with have melted the case of the pack just around the plug (packs still work fine though), because of the plugs getting lose, and it happened to someone else on here a few weeks ago. I haven't had that problem with mine, but I do have the bend the springs back out on the balance leads, because they sometimes loose contact and stop the charge, even though everything's still plugged in. Haven't had it cause a slow charge like yours though, just stops altogether.