Please help us help you and fill where relevant:
Your LimeSurvey version:6.3.4
Own server
Survey theme/template: Fruity
==================
Currently the logo_pdf.png prints way too big on the "Export PDF". I'm not talking about QueXML PDF. I mean the "export pdf" button on the top left of a completed survey.  I've tried making the logo_pdf.png image smaller but Limesurvey just increased it to fill in the space. I've looked at config_defaults.php and nothing I change there helps. 
The problem is it's being expanded by the software to make it 4 times larger that it will fit in the header and so only the top of the image shows. It's the same with the default Limesurvey logo.  Where is the setting for that and I'll just go in and manually change it? Thanks