When printing packing slips for consecutive orders entered for the same bill-to, some, but not all packing slips print without starting a new page and a new header.
To avoid this, I have to print each one individually.
Does anybody else experience this?

Yes, we have noticed this behavior for some time now.  Just went to printing every one individually.
 
Mikeb

should have mentioned;
classic, slightly modified RTM 4

Sounds like a problem with the Group Break in the RTM.  The Group Break is the field the report uses to page break between SOs.  Open up the rtm with the forms editor.  Click on the REPORT menu and then select Groups.  This will open a Groups window which will display a list of existing group breaks.  Group[0] should be set to BKAR.INV.SONUM and group[1] should be set to MULTI.LOC.BREAK.  Change the group field by clicking on the group you want to change and then select the new group break from the list of available fields.  Click Ok when you are done and then save the RTM.  Make sure you are on the Main page when saving otherwise it may trash the RTM.
Note: For RTMs with only one group, follow the same directions and change the group to BKAR.INV.SONUM.
 
Mike