I have reports with subreports where the sub reports get hidden based on critieria. One report has several sub reports each in a group of some sort.

The first group header (which in this is sort of the page header) has some page numbering and a couple of other bits of info including a group number.  When the group changes, normally it's a clean changeover. However with one group I get a doubling up of this info at the top of the page Which to me says that there is some sort of output.

However if I remove the "on format" for that group footer (in this case), it prints normally. There is no code in the "on format" procedure (yet) and the groupfooter is set to hidden. I have removed the sub report and get the same output. If I remove the "on format' precedure from the properties, it works fine, no overlap. The group has no header.

Can someone point me in the right direction please. I can't get any balder.