Some data from the apps need to be encoded in base64 first, then sent to Kafka. Currently, this is being used for the audio input in the active RMT app.
The data sent will look like this (ellipsis added for brevity):
Decoding base64 encoded data
There are various ways to decoded this data, but one easy way to manually decode individual data would be to use this online decoder: https://opinionatedgeek.com/Codecs/Base64Decoder, then paste the encoded data without the data type information:
Click Decode, rename the file name next to 'Click here to download decoded file as' to 'your-file-name.m4a', then download the file.