Incorrect vendor image path in PDF invoice

[capricornio]

When trying to create an invoice in the BE I get this error:
TCPDF ERROR: [Image] Unable to get image: /home/vhosts/[sitename]/httpdocs/images/stories/virtuemart/vendor/resized/logo_150x150.jpg

Since I've installed Joomla in a folder named joomla under httpdocs, I can understand this error-message, but why is the whole path loaded instead of basepath/images/.... ?

How to solve this ? Changing the Vendor Media URL did not help me.