Bi-linear filtering not always working when sourcing Images directly as textures

import QtQuick 2.0

Rectangle {
    width: 400
    height: 400
    color: "white"

    Image {
        id: src
        source: "images/butterfly.png"
        anchors.fill: parent
        smooth: true
        visible: false
    }

    Image {
        id: src2
        source: "images/butterfly.png"
        anchors.fill: parent
        smooth: true
        visible: false
    }

    ShaderEffect {
        id: effect
        property variant source: src
        anchors.fill: parent
    }

    MouseArea {
        anchors.fill: parent
        onClicked: effect.source = src2
    }
}