Performance Problem with Excel+AnalyisAddIn

Hello Experts,

“suddenly” I am facing huge performance problems when I work with Excel+AddIn. My Excel contains several data sources, some macros, named
ranges and a pivot table. When I do actions like:

• Open document (no auto-update)
• Save as (+ after enter of new file name)
• Enter/changing formula like “=SAPListOfVariables("DS_2";"TEXT")”

the effect is, than

• CPU-usage jumps to max
• Excel is frozen (5-30 minutes)

When I work without the AddIn in "normal Excel" I have no problems. When I activate the AddIn via macro then the effects starting here too.

Any idea what Excel/the Addin is “really doing” and, even more interesting, how to avoid it?

Thanks,

Stephan