Col Axis Expansion error / correction via button

Hi all,

we're using EPM 10 for MS SP 14 Patch 3 .NET 3.5.

I have a report where I have my year in the column axis. Actually, I wanted to show Context + Base Members (= month) in my Columns, but whenever I click the Refresh Button, the selection changes to Context + Member, so that only the year is visible. Has anybody ever seen this behaviour? And my second question is, when this cannot be changed, how can I create a Button that does the expansion to the Base level, so that the users don't have to click through all quarters to get their 12 months?

Thanks a lot,

Philipp