Terrain trace collision bugged

So i’ve made an RTS style drag box selection. I am using “Get hit result under cursor by Channel” to get the coordinates.

Now the problem is that when I am using terrain as my plane for units AND I move my player camera more than 1500 units away from the terrain the hit result often returns 0,0,0 as the vector coordinates which causes the drag box to stutter a LOT. If I move the camera closer - say 1000 units - above ground everything works flawlessly. If I use something other than terrain as the plane for my units to move on, everything works all the time no matter the camera distance. What could be the problem and how can I fix this?