Yes, Text Speaker will allow you to include a background music track in your speech file. Several different formats are supported for background music files.
Follow these steps to add background music:
1. Click on "Convert To Audio" from tool bar, you will get this dialog
2. Enable the option
Add background music to the output file.
Click on the 'Browse' button to select your music file and click 'Test' to listen to how it sounds. You can adjust the volume with the help of the slider.