In case you started using Bela before the recent overhaul of the core API, then you probably want to update your code to the latest API.
Here is a link to the page of the Wiki that should help you doing just that:
https://github.com/BelaPlatform/Bela/wiki/Porting-your-code-from-the-old-BeagleRT-API
Also, do not forget to to pull the latest source code from here. The old repository on soundsoftware.ac.uk has been discontinued and the project was moved to github:
https://github.com/BelaPlatform/Bela
Let us know if you have any trouble.
