Unity - Mecanim & Rigidbody on Third Person Controller - Gravity bug?

Question

I'm working on a third person controller which uses physX to interact with the other objects (using the Rigidbody component) and Mecanim to animate the character.

All the animations used are baked to Y, and the movement on this axis is controlled by the gravity applied by the rigidbody component.

The configuration of the falling animation:

And the character components configuration:

Since the falling animation doesn't have root motion on XZ, I move the character on XZ by code. Like this:

    // On the Ground
    if (IsGrounded())
    {
        GroundedMovementMgm();

        // Stores the velocity
        velocityPreFalling = rigidbody.velocity;
    }
    // Mid-Air
    else
    {
        // Continue the pre falling velocity
        rigidbody.velocity = new Vector3(velocityPreFalling.x, rigidbody.velocity.y, velocityPreFalling.z);
    }

The problem is that when the chracter starts falling and hit against a wall in mid air, it gets stuck to the wall. Here are some pics which explains the problems:

Hope someone can help me. Thanks and sory for my bad english!

PD.: I was asked for the IsGrounded() function, so I'm adding it:

    void OnCollisionEnter(Collision collision)
    {
        if (!grounded)
            TrackGrounded(collision);
    }

    void OnCollisionStay(Collision collision)
    {
        TrackGrounded(collision);
    }

    void OnCollisionExit()
    {
        grounded = false;
    }

    public bool IsGrounded()
    {
        return grounded;
    }

    private void TrackGrounded(Collision collision)
    {
        var maxHeight = capCollider.bounds.min.y + capCollider.radius * .9f;
        foreach (var contact in collision.contacts)
        {
            if (contact.point.y < maxHeight && Vector3.Angle(contact.normal, Vector3.up) < maxSlopeAngle)
            {
                grounded = true;
                break;
            }
        }
    }

I'll also add a LINK to download the project if someone wants it.

Answer 1

The problem was caused by the friction configuration on the character's physic material. Changing it as the image shows fixed the problem:

It seems that over .001 of dynamic friction and .01 of static are enough to start slowing the fall of the character when hitting a wall.

Answer 2

Most of the mecanim setup stuff is irrelevant; this question mostly rests on what IsGrounded() is doing. Whatever is happening in there to detect the ground is not working correctly, and it considers hitting the wall to be "on the ground".