\unfold repeat question

[Jule Slootbeek]

Hi,
when i try to do this:

    treble = {
        \notes\relative c'' {
        \clef treble
            \repeat unfold 8 {<fis,8 d8 a8>} | r1 | r1
        }
    }

i get this error 8 times:

warning: Too many clashing notecolumns.  Ignoring them.

it precedes to print the three notes in a chord, but the stems are not 
one, so it looks like a single 32nd note printed 8 times, while i want a 
2 beamed sets of 4 8th notes..
in the docs i also couldn't find a good example of \repeat unfold, only 
a mention under the  \repeat section (w/out an example) and in the piano 
excerpt but there it is used before \notes.

any ideas?

Jule

and then it prints out
Jule Slootbeek
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