Midi repeats

[Peter Gentry]

The individual music files all contain volta repeats and the score pdf is 
produced correctly but the MIDI output does not include
repeats.

Where am I going wrong.

\version "2.16.0"
\score {
\unfoldRepeats 
  << 
    <<
      \new Staff = "Oboe"
      <<
        \new Voice = "Flute"  {  
          \set Staff.midiInstrument = "flute"
           << \include "Cass_Cc_M5_L1.ly" >> }
      >>
      \new Staff = "Clarinet"
      <<
        \new Voice = "Clarinet"  {  \transposition bes  
         \set Staff.midiInstrument = "clarinet"
          << \include "Cass_Bb_M5_L2.ly" >> }
      >>
      \new Staff = "French Horn"
      <<
        \new Voice = "Clarinet"  { \transposition bes  
         \set Staff.midiInstrument = "clarinet" << \include "Cass_Bb_M5_L3.ly" 
>> }
      >>
      \new Staff = "Bassoon"
      <<
        \new Voice = "Bass"  { \transposition bes,  
         \set Staff.midiInstrument = "clarinet" 
         << \include "Cass_BBb_M5_L4.ly" >> }
      >>
    >>
  >>
 \midi { }
}


regards
Peter Gentry