private void TestInsertMode()
{
int hr;
TimelineInsertMode m;
// E_NOTIMPL
hr = m_pTimeline.SetInsertMode(TimelineInsertMode.Insert);
//DsError.ThrowExceptionForHR(hr);
hr = m_pTimeline.GetInsertMode(out m);
DsError.ThrowExceptionForHR(hr);
Debug.Assert(TimelineInsertMode.Overlay == m, "TimelineInsertMode");
}