Jumping increases movement speed

I’m making a game with ball physics and an FPS camera. I have this bug where the player’s movement
is increased when I jump.

Example:

Running along the Z axis on a plane:167321-runstrt.png

Suddenly jumping: 167322-runjump.png

My code:

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class PlayerControl : MonoBehaviour
{
    public Camera cam;
    public float camDir;
    public Rigidbody rb;
    public float speed;
    float moveFwrd;
    float moveSide;
    public KeyCode jumpKey;
    public KeyCode brakeKey;
    public float jumpSpeed;
    public float brakeForce=5f;
    float DistanceToTheGround;
    // Start is called before the first frame update
    void Start()
    {
        DistanceToTheGround = GetComponent<Collider>().bounds.extents.y;
    }

    void Update()
    {
        // Input
        moveFwrd = Input.GetAxis("Horizontal");
        moveSide = Input.GetAxis("Vertical");

        // Player Jump
        if (Input.GetKeyDown(jumpKey) && Physics.Raycast(transform.position, Vector3.down, DistanceToTheGround + 0.1f))
        {
            rb.AddForce(Vector3.up * jumpSpeed, ForceMode.Impulse);
        }

        // Braking
        if (Input.GetKey(brakeKey))
        {
            rb.angularDrag = brakeForce;
        }
        else
        {
            rb.angularDrag = 0.01f;
        }
    }

    
    void FixedUpdate()
    {
        // Player Movement
        Vector3 movement = cam.transform.right * moveFwrd + cam.transform.forward * moveSide;

        movement = movement.normalized;

        rb.AddForce(movement * speed);
    }
}

This is because of the friction between the floor and your player. In the air, there is (I suppose you haven’t changed it) no drag. That’s why it moves quicker in air than on ground. Also, if you’re in the air, you will be accelerating your object because there are no forces to counteract this. I’d suggest you reduce the force added to zero when the velocity of the rigidbody approaches the maximum speed imposed.

For example:

void FixedUpdate()
     {
         // Player Movement
         Vector3 movement = cam.transform.right * moveFwrd + cam.transform.forward * moveSide;
 
         movement = movement.normalized * maximumSpeed - rb.velocity.magnitude*;
 
         rb.AddForce(movement * speed);
     }