Hello I'm new here. I bought a second hand spark but it was in really great shape. It looked brand new. It flew really great for a month but the last couple days it's. Been jumping up and down, barely responding or not responding to the controller sometimes it tries to land itself and slams itself on the ground(only from at most 18 inches). I haven't done any mods or changed the way I connect to it since day one. The only thing is I put in a SD card. But the problems were presenting themselves before that. I connect with a lil 90° data cable after the drone and controller connect. And it's flown beautifully. I dunno how or where to start looking for the problem. Any and all help would be appreciated! Thank you!