Question Raycast Very Inaccurate?

Hiya, so my project was fine yesterday and I opened it up today and found the raycasts were very inaccurate. If the raycast hit anywhere near the edge of a block (by this i mean anywhere that is not near the center) it will pass right through. I'm also getting weird things like the raycast hitting two objects simultaneously, despite not being anywhere near the conditions that could possibly create that. I don't know what's up. Here's a picture of it in action:
https://imgur.com/YP0BEyK (Sorry for no embed, forums don't seem to like gifs.)

For context, Machine(Clone) is the bottom block. Swinger Servo(Clone) is the block that's just out of frame. I don't know what is wrong. The crosshair is clearly on the machine but it's spitting out two. I've made sure it's not accidentally coming out offset or whatnot. I literally have no clue what is wrong.

If anyone wants to take a look at the code:

Code (CSharp):

1. if (Physics.Raycast(cam.transform.position, cam.transform.forward,out RaycastHit hit, 200f, buildLayers))
2.         {
3.             //This isn't the issue. If this was a issue the MouseOver wouldn't be set, but it is being set. Just to the wrong thing.
4.             if (GameUI.instance.UIUnderMouse())
5.                 return;
6.             MouseOver = hit.collider.gameObject;
7.             mouseOverPoint = hit.point;
8.         }
9.         else
10.         {
11.             MouseOver = null;
12.         }

 

The easiest thing to do will be to use debug draw ray or draw line to visualise exactly where the ray is currently aiming: https://docs.unity3d.com/ScriptReference/Debug.DrawRay.html

You also say that the gameUI line isnt the issue, but for sanity sake comment that part out & test without it.

You could also try using: https://docs.unity3d.com/Manual/CameraRays.html as it takes into account the cameras view frustrum, instead of using Input.mousePosition use ViewportToRay & pass in 0.5f, 0.5f for the centre.

Hopefully this helps your work out your problem.