DrumStaff question

[Menu Jacques]

Hello folks,

I can’t seem to get why the code below produces an empty 5-line first staff.

Thanks for your help!

JM

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\version "2.19.80"

\header {
  title                   = "basic/UnpitchedTuplet.xml"
  software           = "MuseScore 2.0.3.1"
  encodingDate                   = "2017-05-20"
}

\paper {
  indent               = 3\cm
}

\layout {
  \context {
    \Score
    autoBeaming = ##f % to display tuplets brackets
  }
}

P_PFour_Staff_One_Voice_One = \relative {
  \language "nederlands"
  \key c \major
  \clef "percussion"

  \stopStaff
  \override Staff.StaffSymbol.line-count = 1
   \startStaff
  \numericTimeSignature \time 4/4
  \stemDown e4 r \once \omit TupletBracket
  \tuplet 3/2 { e8 [ :16 e e ] }
  \once \omit TupletBracket
  \tuplet 3/2 { e8 [ :16 e e ] }

  \bar "|." |
}

\score {
  <<

    \new DrumStaff = "P_PFour_Staff_One"
    \with {
      instrumentName = "Snare Drum 4"
      shortInstrumentName = "Sn. Dr."
    }
    \drummode
    {%<<
      \context Voice = "P_PFour_Staff_One_Voice_One" <<
        \P_PFour_Staff_One_Voice_One
      >>
  }%  >>
  >>

  \layout {
    \context {
      \Score
    }
  }

  \midi {
    \tempo 4 = 90
  }
}

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