Class priority when debugging

I have a Java module that, by necessity, contains some classes with the same package and name as some classes in one of its maven dependencies.

When I debug one of these classes the debugger hits my breakpoint set on the module version of the class but displays the source from the maven dependency jar.

I have ensured that <Module source> is above the Maven jar in the module settings -> dependencies tab but the precedence set there doesn't appear to affect debugging.

Does anyone know if I can tell the IDE which sources to use or specify the priority of the sources that the debugger uses?

Thanks in advance.