You are correct the, DSP is a separate processor within the CSR8675. It has its on program and data memory.
All image are taken from the linked datasheet.
The DSP (Digital Signal Processor) is a dedicated processor. It has additional hardware units, parallel instruction execution support that gives you a better platform with better performance to process ...
The code shows a controlled transfer from source to receiver, but notice that I artificially or independently generate a MESSAGE_MORE_DATA message every 100 milliseconds.
Before sending, use the function:
In the method main(), before the first message. In my case, it helped. Write if it helped you. For example, in your case it looks like this: MessageSinkTask (audSink_L,task).