Physics AddForce reduced when 3 objects are colliding

I am Going through ETeeskiTutorials fps and I am just finnishing up the Rigid body character controller movement script and I have run into a problem. When my character is running around everything seems to be happening as it should, but when the character is touching 2 seperate surfaces (like the floor and a wall, or the seam where two diffrently angled floors are touching) I notice a dramatic reduction in the addition of force to the character. Most noticeably when jumping. Here are the Scripts I am using.

This one is for Camera look:

 var lookSensitivity : float = 5;
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 var yRotation : float;
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 var xRotation : float;
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 var currentYRotation : float;
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 var currentXRotation : float;
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 var yRotationV : float;
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 var xRotationV : float;
 var lookSmoothDamp : float = 0.045;
 
 function Update () {
     yRotation += Input.GetAxis("Mouse X") * lookSensitivity;
     xRotation -= Input.GetAxis("Mouse Y") * lookSensitivity;
     
     currentXRotation = Mathf.SmoothDamp(currentXRotation, xRotation, xRotationV, lookSmoothDamp);
     currentYRotation = Mathf.SmoothDamp(currentYRotation, yRotation, yRotationV, lookSmoothDamp);
     
     xRotation = Mathf.Clamp(xRotation, -90, 90);
     
     transform.rotation = Quaternion.Euler(currentXRotation, currentYRotation, 0);
 }

and this one is for movement and jumping:

 var walkAcceleration : float = 45;
 var runDeceleration : float = 1;
 var walkDecelerationVolX : float;
 var walkDecelerationVolZ : float;
 var walkDeceleration : float = 0.5;
 var cameraObject : GameObject;
 var maxWalkSpeed : float = 3;
 var horizontalMovement : Vector2;
 var jumpVelocity : float = 300;
 var grounded : boolean = false;
 var maxSlope : float = 60;
 
 function Update () 
 {
 
 //faces the rigidbody with the camera//
     transform.rotation = Quaternion.Euler(0, cameraObject.GetComponent(MouseLookScript).currentYRotation, 0);
 
 //gets current speed as a Vector2//
     horizontalMovement = Vector2(rigidbody.velocity.x, rigidbody.velocity.z);
     //sets a percentage that is inversely proportional to the speed over maxWalkSpeed//
     if(horizontalMovement.magnitude > maxWalkSpeed)
     {
         runDeceleration = maxWalkSpeed / horizontalMovement.magnitude;
     } 
     //Keeps runDecceleration from getting stuck at a low percentage in the event of sudden decceleration//
     else
     {
         runDeceleration = 1;
     }
     
     walkDeceleration = horizontalMovement.magnitude / 25 + 0.1;
     //dampend character slide//
     if(grounded)
     {
         rigidbody.velocity.x = Mathf.SmoothDamp(rigidbody.velocity.x, 0, walkDecelerationVolX, walkDeceleration);
         rigidbody.velocity.z = Mathf.SmoothDamp(rigidbody.velocity.z, 0, walkDecelerationVolZ, walkDeceleration);
     }
     
     //wasd movement//
     rigidbody.AddRelativeForce(Input.GetAxis("Horizontal") * walkAcceleration * runDeceleration, 0, Input.GetAxis("Vertical") * walkAcceleration * runDeceleration);
     
 //Jumping//
     if(Input.GetButtonDown("Jump") && grounded)
     {
         rigidbody.AddForce(0, jumpVelocity, 0);
     }
     
 
 }
 //Jumping Prerequisits//
 function OnCollisionStay(collision : Collision)
 {
 
     for(var contact : ContactPoint in collision.contacts)
     {
         if(Vector3.Angle(contact.normal, Vector3.up) < maxSlope)
         {
             grounded = true;
         }
     }
 }
 
 function OnCollisionExit()
 {
     grounded = false;
 }

I am not sure if it is just a quark with the physics engine adding the friction in a funny way when dealing with this situation or if I am approaching the code in a weird way. I have kind of done a bit of modification of it from the original tutorial. Any ways any insight into this anomaly would be greatly appreciated, thanks. :)