It's easy to get custom audio on MARCo Online and sync it to your MARCo device!
Click on the shopping cart icon on the main menu.
Then, click on the section for audio.
Scroll through the list of audio files that appears and tap on one you'd like to choose to examine it. The store item will scale up and you'll be able to see a description, the sample audio file to play, and whether or not you can purchase it. If you have enough MARCoins, click "Purchase" to get the sound. You will get a confirmation notice if it goes through.
Click on the settings icon from the main menu.
Click the tab that says "Customize Settings." If you scroll down, you will see the options for background audio appear. You can set the volume of the background audio by pressing "+" or "-" on the volume bar at the top. Scroll down through the audio files and select the one you want by tapping on it.
Now the desired audio should start playing! If you can't hear it, try raising the background audio volume.
NOTE: There is a known bug on certain devices where users may experience a delay in loading audio after purchasing audio from the MARCo Market that prevent the audio from being immediately playable. If you find you cannot select a newly purchased audio file, simply refresh/restart the app, and it will be playable the next time you load. Our team is actively working on a fix to this.