Gazebo Diff drive can make the robot stay immobile

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Hi, I'm trying to build a robot in gazebo9 with Ros2-dashing. I'm using the libgazebo_ros_diff_drive plugin to control the wheels and give instructions to the robot.

The controls work greats and I can move the robot around in the virtual world, but when I don't give cmd_vel (or 0 in all directions) diff drive make the wheels turn slowly, moving the robot. I am almost certain that's diff drive who does the moving, as it won't happen if I remove the plugin (The robot don't slide otherwise ).

  <gazebo>
<plugin name="robot_diff_drive" filename="libgazebo_ros_diff_drive.so">

  <ros>
    <namespace>/drive</namespace>
    <!--<argument>cmd_vel:=cmd_vel</argument>
    <argument>odom:=odom</argument>-->
  </ros>

  <update_rate>30</update_rate>

  <!-- wheels -->
  <left_joint>wheel_left_joint</left_joint>
  <right_joint>wheel_right_joint</right_joint>

  <!-- kinematics -->
  <wheel_separation>0.434</wheel_separation>
  <wheel_diameter>0.2</wheel_diameter>

  <!-- limits -->
  <max_wheel_torque>20</max_wheel_torque>
  <max_wheel_acceleration>1.0</max_wheel_acceleration>

  <command_topic>cmd_vel</command_topic>

  <!-- output -->
  <publish_odom>true</publish_odom>
  <publish_odom_tf>true</publish_odom_tf>
  <publish_wheel_tf>false</publish_wheel_tf>

  <odometry_topic>odom</odometry_topic>
  <odometry_frame>odom</odometry_frame>
  <robot_base_frame>base_footprint</robot_base_frame>

</plugin>

</gazebo>

Here the config of the diff drive, they are mostly the same as the turtlebot3. And the wheels :

    <xacro:macro name="origin_wheel">
        <origin rpy="${rpy}" xyz="${xyz}"/>
    </xacro:macro>

    <link name="wheel_${name}_link">
        <inertial>
            <xacro:origin_base />
            <mass value="${wheel_mass}" />
            <inertia ixx="0.0016" ixy="0" ixz="0" iyy="0.0016" iyz="0" izz="0.003" /><!-- Good value of inertia -->
        </inertial>

        <collision>
            <xacro:origin_base />
            <geometry>
                <cylinder radius="${wheel_radius}" length="${wheel_length}"/>
            </geometry>
        </collision>

        <visual>
            <xacro:origin_base />
            <geometry>
                    <cylinder radius="${wheel_radius}" length="${wheel_length}"/>
            </geometry>
            <material name="green"/>
        </visual>
    </link>
    <gazebo reference="wheel_${name}_link">
        <turnGravityOff>false</turnGravityOff>
        <mu1>10000.0</mu1>
        <mu2>10000.5</mu2>
        <kp value="${kp}" />
        <kd value="${kd}" />
        <material>Gazebo/Gold </material>
    </gazebo>

    <joint name="wheel_${name}_joint" type="continuous">
        <parent link="reverse_footprint_link"/>
        <child link="wheel_${name}_link"/>
        <xacro:origin_wheel />
        <axis xyz="0 0 1"/>
    </joint>

Does anyone know where I can look to found a solution, or what to do to make it work as I need? (Also, I don't know if it's a question better suited to ros answers or gazebo answers :/ )

Thank :)