Remove option to expand a member in Matrix

Hi all,

I have an issue when working with the built-in Matrix visual.

I would like to have certain members of a matrix collapsed as a default, wheras other members should be expanded as a default.

Example: I have a simple 2 level hierarchy in rows in my matrix: "Main Account" and "Account"

Hierarchy:

Main Account                   Account

Sales                                 Sales Area East

Sales                                 Sales Area West

COGS                                COGS Area East

COGS                                COGS Area West

Gross Margin                    Gross Margin East

Gross Margin                    Gross Margin West

Using the Matrix visual i wish to show 2 Main Account members (Sales and COGS) expanded to the Account. And Gross Margin should always be collapsed:

- Sales

      Sales Area East

      Sales Area West

- COGS

      COGS Area East

      COGS Area West

+ Gross Margin

When I change a slicer value (e.g. changing period or accounting manager), all members are expanded (including Gross Margin).

Is there a way to either prohibit a single member from being expanded (no "+" available for that particular member) or to default an expand/collapse layout? (or maybe a third option...?).

BR

Morten