OSX Audio Application

I want an application that is capable of sending/receiving audio and MIDI data. The goal is later to host other audio plugins. So in this first step there just should be an application which has 1 or 2 dialogs to choose the audio and midi driver. The application should be written in C++ with XCode. There should be an easy interface to get the audio and midi callbacks. ## Deliverables germany location (berlin) is a plus. german language is a plus. english language is required.