rob
found a way to Git's update zip, put it into place and it didn't make much difference, but the code changed.
form the one line in the article:
<h2>{fabrik view=element list=7 rowid=4 element=programmaas___soort}</h2>
now came a dbjoin-description instead of FormTip messade as before.
<h2>Cursus <div class="dbjoin-description"><div style="display:" class="notice description-1">Cursus</div><div style="display:none" class="notice description-2">Lezing</div><div style="display:none" class="notice description-3">Opleiding</div><div style="display:none" class="notice description-4">Workshop</div></div></h2>
Then I had the idea to once more go through all the settings of the element.
I have it in 4 different lists all pointing to the same table.
I put them all four in an article and saw that only once the element had this problem.
By compare and adjusting the settings I found that in Details -> Advanced in Description field 'soort' (the name of the element) was selected.
Changing it to 'Please select'
solved the problem.
So, problably no further investigation needed.
thanks for your help.
mno