Is there a data source for phone call surveys in C4C

recently SAP have given us the ability to link surveys to phone calls in C4C however i'm struggling to find/create a data source that contains both survey info and phone call info so I can reports on this (I know there is one specifically for visit surveys).

I've tried to create a data source using survey answers & phone call data sources however there are no common fields to link them together from what I can see so it doesn't work.

is anyone aware of a data source/report that already exists or of a way I can create a data source to build reports over?