Domain Access: shown content after login

Hi out there,
I've just installed and tested Domain Access Modul a few days ago and it works fine for me (Domain Configuration, Domain Content also active).
For each subdomain only the aggregated content is visible. Ja, fine.

Problem is that user see all the content after login to the site. There is no filtering for the subs. The domain access settings for each user appears to be correct.

My target is to filter the content for each site no matter if the user is logged in or not e.g.:

sub1.domain.com: show all content flagged for sub1

sub2.domain.com: show all content flagged for sub2

A user default domain is sub1.domain.com, so after the login only this content shows up.

Is there a setting or working step to get this done?
I' ve tried some settings but nothing helps with my target.

Thanks

Bob