panning in timidity wrong

[karl]

 I'm using:

\version "2.19.0"

midi_a = {
  \set Staff.midiInstrument = #"electric bass (finger)" % 34
  \set Staff.midiPanPosition = #-1
}
midi_b = {
  \set Staff.midiInstrument = #"electric bass (finger)" % 34
  \set Staff.midiPanPosition = #0
}
midi_c = {
  \set Staff.midiInstrument = #"electric bass (finger)" % 34
  \set Staff.midiPanPosition = #1
}

ma = \relative c'' {
  \midi_a
  c4 b a g | R1*2 |
}
mb = \relative a' {
  \midi_b
  R1 | g4 f e d | R1 |
}
mc = \relative a, {
  \midi_c
  R1*2 | d4 c b c |
}

\score {
  <<
    \new Staff \ma
    \new Staff \mb
    \new Staff \mc
  >>
  \midi { }
}

 (midiPanPosition is documented in the internals doc, under 
 2.2.72 Midi control function performer)

 The midi file looks good, but when I run it through timidity
 \ma sound in the middle, \mb and \mc to the right. Commenting away
 the midiInstrument, the panning comes out as it should.

 Has anyone experienced this, can anyone recommend another midiplayer?

Hälsningar,
/Karl Hammar

-----------------------------------------------------------------------
Aspö Data
Lilla Aspö 148
S-742 94 Östhammar
Sverige
0173 140 57