Teamcity notifications for failed builds triggered for commits merged from master when using Git

I have the following problem:

User A has commited to master
User B merged master to feature branchA and the build fails

User A is notified although he only commited to master

The issue is caused by Teamcity thinking that all the commites in the merge belong to BranchA so he thinks that User A was responsible to the build breaking

How can this be fixed?

This is a big problem as we have many features and many developers

We are using TC 7 and Git