Hi Petrika, thanks for the compliments!
The original Bela cape for the BeagleBone Black does work as a drop-in replacement for the old BB audio cape and it is possible to use it with a sample rate of 96kHz through ALSA.
There are a few caveats to this though. By using ALSA you do not get the ultra low-latency performance of Bela, nor can you use any of our user-facing software (for example the IDE and scope etc). It is also not easy to use the analog and digital i/o of the Bela cape with audio input from ALSA. We do not actively support the use of ALSA with our products, and it is not compatible with our latest images (v0.3.x) so you must use older releases (v0.2.x) from here.
If you prefer you can port your application to use our API instead of ALSA, however this is not quite as easy as recompiling it against our libraries. Instead you will need to modify your ALSA audio callback to be compatible with our API, and also ensure your code is safe to run within Bela's real-time environment. If you wish to do this we can offer advice and troubleshooting support.
The maximum audio sample rate using the Bela API is currently 44.1kHz, however with the audio expander capelet it is possible to use Bela's analog i/o for audio signals at 88.2kHz, see here for a more in-depth discussion of this.
For detailed documentation on Bela take a look at our wiki.