I have two data sources (Oracle and Excel) and two linking dimensions (I added them to details). Data sources are connected properly as I see proper icon (orange paper clip) when I try to change typ of chart the data sources disconnects.
Then I can connect them once more and everything is ok till I change type of chart... what could be wrong?
Are your field names the same between the sources? This helps greatly. You don't need to change the source names - you can use an alias.