WTTB.  If you are just trying to get it to "barely" hover it might just be moving to ground effect, wind, torque, etc. There are many adjustments that play together that need to be aligned to get a stable hover.  Even the RTF models will generally need some tweaks to get the blades tracking, etc.  I'd recommend using a pitch gauge to ensure the paddles and the blades are set correctly as a first step.  Good luck and be patient, it can take a little time!