PyQt4 scrollbar interacts incorrectly with embedde

I'm having an issue combining PyQt4 scrollbars (on the MainWindow) with embedded scenes - everything works fine until I resize my window, after which my scenes begin to travel with the scrollbar off the page.

Below is the simplified, full code to illustrate this behavior (with two screenshots attached afterward to explicitly showcase this interaction):

import sys, os
from pyface.qt import QtGui, QtCore
os.environ['ETS_TOOLKIT'] = 'qt4'

from traits.api import HasTraits,Instance,on_trait_change
from traitsui.api import View,Item
from mayavi import mlab
from mayavi.core.ui.api import MayaviScene, MlabSceneModel, SceneEditor

class Mayavi_Scene(HasTraits):
    scene = Instance(MlabSceneModel, ())

    @on_trait_change('scene.activated')
    def update_scene(self):
        Mayavi_Scene.fig1 = mlab.figure(1, bgcolor=(.5,.5,.5))
        self.scene.mlab.clf(figure=Mayavi_Scene.fig1)
        testPlot = mlab.test_contour3d()

    view = View(Item('scene', editor = SceneEditor(scene_class=MayaviScene),
                    height=300, width=300, show_label=False),
                resizable=True,
                )

class P1(QtGui.QWidget):
    def __init__(self, parent=None):
        super(P1, self).__init__(parent)
        layout = QtGui.QGridLayout(self)
        layout.setContentsMargins(20,20,20,20)
        layout.setSpacing(10)

        self.label_edge1 = QtGui.QLabel('')
        self.label_edge1.setMargin(5)
        self.label_edge1.setFrameStyle(QtGui.QFrame.Panel | QtGui.QFrame.Sunken)
        layout.addWidget(self.label_edge1, 0, 0, 10, 10)
        self.label_edge1.show()

        self.label_avgVol = QtGui.QLabel('Test')
        self.label_avgVol.setMargin(5)
        self.label_avgVol.setFrameStyle(QtGui.QFrame.Box | QtGui.QFrame.Sunken)
        self.label_avgVol.setAlignment(QtCore.Qt.AlignCenter | QtCore.Qt.AlignVCenter)
        layout.addWidget(self.label_avgVol, 0, 0, 1, 10)
        self.label_avgVol.show()

        self.viz1 = Mayavi_Scene()
        self.ui1 = self.viz1.edit_traits(parent=self, kind='subpanel').control
        layout.addWidget(self.ui1, 1, 1, 1, 9)

class P2(QtGui.QWidget):    
    def __init__(self, parent=None):
        super(P2, self).__init__(parent)
        layout = QtGui.QGridLayout(self)
        layout.setContentsMargins(20,20,20,20)
        layout.setSpacing(10)

class MainWindow(QtGui.QMainWindow):
    def __init__(self, parent=None):
        super(MainWindow, self).__init__(parent)
        self.setGeometry(50, 50, 500, 500)   

        tab1 = P1(self)
        tab2 = P2(self)

        self.tabs = QtGui.QTabWidget(self)
        self.tabs.resize(250,150)

        self.tabs.addTab(tab1, 'Page 1')
        self.tabs.addTab(tab2, 'Page 2')

        self.setWindowTitle('SCROLLBAR ERROR EXAMPLE')

        self.groupscroll = QtGui.QHBoxLayout()
        self.groupscrollbox = QtGui.QGroupBox()

        self.MVB = QtGui.QVBoxLayout()
        self.MVB.addWidget(self.tabs)

        scroll = QtGui.QScrollArea()
        widget = QtGui.QWidget(self)
        widget.setLayout(QtGui.QHBoxLayout())
        widget.layout().addWidget(self.groupscrollbox)
        scroll.setWidget(widget)
        scroll.setWidgetResizable(True)
        self.groupscrollbox.setLayout(self.MVB)
        self.groupscroll.addWidget(scroll)
        self.setCentralWidget(scroll)
        self.show()

if __name__ == '__main__':
    app = QtGui.QApplication.instance()
    w = MainWindow()
    sys.exit(app.exec_())

Before Reframing

After Reframing

Edit: .gif to show effect (notice how object gets covered up by its own frame containing it at the end instead of moving with it; it's like the 3d scene object isn't being notified that everything else around it is changing):

I modified the place where the scroll bars are added.

import sys, os
from pyface.qt import QtGui, QtCore
os.environ['ETS_TOOLKIT'] = 'qt4'

from traits.api import HasTraits,Instance,on_trait_change
from traitsui.api import View,Item
from mayavi import mlab
from mayavi.core.ui.api import MayaviScene, MlabSceneModel, SceneEditor

class Mayavi_Scene(HasTraits):
    scene = Instance(MlabSceneModel, ())

    @on_trait_change('scene.activated')
    def update_scene(self):
        Mayavi_Scene.fig1 = mlab.figure(1, bgcolor=(.5,.5,.5))
        self.scene.mlab.clf(figure=Mayavi_Scene.fig1)
        testPlot = mlab.test_contour3d()

    view = View(Item('scene', editor = SceneEditor(scene_class=MayaviScene),
                    height=300, width=300, show_label=False),
                resizable=True,
                )

class P1(QtGui.QWidget):
    def __init__(self, parent=None):
        super(P1, self).__init__(parent)
        layout = QtGui.QGridLayout(self)
        layout.setContentsMargins(20,20,20,20)
        layout.setSpacing(10)

        self.label_edge1 = QtGui.QLabel('')
        self.label_edge1.setMargin(5)
        self.label_edge1.setFrameStyle(QtGui.QFrame.Panel | QtGui.QFrame.Sunken)
        layout.addWidget(self.label_edge1, 0, 0, 10, 10)
        self.label_edge1.show()

        self.label_avgVol = QtGui.QLabel('Test')
        self.label_avgVol.setMargin(5)
        self.label_avgVol.setFrameStyle(QtGui.QFrame.Box | QtGui.QFrame.Sunken)
        self.label_avgVol.setAlignment(QtCore.Qt.AlignCenter | QtCore.Qt.AlignVCenter)
        layout.addWidget(self.label_avgVol, 0, 0, 1, 10)
        self.label_avgVol.show()



        self.groupscroll = QtGui.QHBoxLayout()
        self.groupscrollbox = QtGui.QGroupBox()



        self.viz1 = Mayavi_Scene()
        self.ui1 = self.viz1.edit_traits(parent=self, kind='subpanel').control

        self.MVB = QtGui.QVBoxLayout()
        self.MVB.addWidget(self.ui1)

        scroll = QtGui.QScrollArea()
        widget = QtGui.QWidget(self)
        widget.setLayout(QtGui.QHBoxLayout())
        widget.layout().addWidget(self.groupscrollbox)
        scroll.setWidget(widget)
        scroll.setWidgetResizable(True)
        self.groupscrollbox.setLayout(self.MVB)
        self.groupscroll.addWidget(scroll)



        layout.addWidget(scroll, 1, 1, 1, 9)



class P2(QtGui.QWidget):    
    def __init__(self, parent=None):
        super(P2, self).__init__(parent)
        layout = QtGui.QGridLayout(self)
        layout.setContentsMargins(20,20,20,20)
        layout.setSpacing(10)

class MainWindow(QtGui.QMainWindow):
    def __init__(self, parent=None):
        super(MainWindow, self).__init__(parent)
        self.setGeometry(50, 50, 500, 500)   

        tab1 = P1(self)
        tab2 = P2(self)

        self.tabs = QtGui.QTabWidget(self)
        self.tabs.resize(250,150)

        self.tabs.addTab(tab1, 'Page 1')
        self.tabs.addTab(tab2, 'Page 2')

        self.setWindowTitle('SCROLLBAR ERROR EXAMPLE')


        self.setCentralWidget(self.tabs)
        self.show()

if __name__ == '__main__':
    app = QtGui.QApplication.instance()
    w = MainWindow()
    sys.exit(app.exec_())

In that condition, the scroll bars are inside the tab and not ouside. Then you get something like :