@puddin86 Older versions of Music Maker used the Magix Low Latency driver which will use the audio device of your computer exclusively. Then no other application can play sound. It could be that you have selected this driver in the program settings. If this is the case you cannot play audio files in another application if Music Maker is still running.
@puddin86 If you used a conventional audio file format like @emmrecs mentioned it should work. In case Music Maker didn't release the audio device after you closed the program it should work fine after a reboot of your computer.