partcombine not fully displaying triplets

[Ole Schmidt]

Dear All,

I were asking a few days ago if there is something wrong with my code  
in the snippet below?
The triplets are not displayed correctly.
(See attached pdf)

best

ole

%%%%%%%%%%%%%%%%%%%%%%%%%
\new Staff  {

\set Staff.printPartCombineTexts = ##f
\time 6/4
\clef "G_8"
\partcombine
\relative c' {  \override TupletBracket #'direction = #up
r4 \times 2/3 { r8 <a e'~>4 } <a e'>2 \times 2/3 { r8 <a e'>4 } <a~  
e'~>4 |
}

\relative c' {  
r1 r4 r8 es,,~ |        
}
}

\version "2.11.36"
%%%%%%%%%%%%%%%%%%%%%%%%