Report couldn't access the data source

Hello!  I'm getting an error when using Power BI Services with a live connection to SSAS.  Yesterday I granted NT AUTHORITY\Authenticated Users with Analaysis Server administrator and at that point I was able to use the report in Power BI Services with the live connection to SSAS.  But I don't thing that it is best practice to grant every user with administrator access to SSAS.  Not only that but I'm trying to implement row level security from SSAS and I believe that if the user has server administrator access then row level security wont have an impact.

I'm just wondering what I'm missing that by giving the user with administrator access to ssas the user can access the live data but when the user does not have administrator access they get the error "Report couldn't access the data source"