[TYPO3-mvc] empty line in front of any output if Plugin active

[Steffen Ritter]

Hi folks,
I currently stumbled about an unknown problem.
If I hide my ExtBased Plugin, all output (in every typeNum) is fine.
If I unhide the plugin, I have an empty line before the <?xml ...> 
definition.

This happens also in other typeNums, where f.e. the the googlemap xml is 
made...

I already checked all my files for empty lines before or after <? ?> 
marks... There is nothing... Any Ideas where this might come from?

regards

Steffen