[NTG-context] Gap above \placefigure[top] ?

Hi, sorry, the next looks so simple, it's probably an often answered thing (I just could not find the answer anywhere…) Why is there a little gap above the figure, though it should be "top". How to avoid it? \starttext \showframe \placefigure[top]{}{\externalfigure[../Figures/Test][frame=off]} \stoptext (With or without figure/path has the same gap) Steffen