5) The user supplies data to the ring buffer during branch playback or memory playback.
Sometimes, taking a large ring buffer will reduce the risk of interruption.
¡The larger the value, the higher the safety for PCM playback, but one task
There is a drawback that the processing time becomes somewhat unstable.
If the entire file is prepared in memory for memory playback, its address and
Specify the file size. In this case, it is not necessary to be an integral multiple of the sector size.
No. 

6) 4096 * 2 [sample / 1ch] is enough for the PCM buffer size unless there is a special reason.
¡By taking this large, when the task function could not be called at the specified frequency
Also, playback may not be disturbed. 

7) The definition of CPU load (CPU occupancy of task function after starting playback) is shown below. 

 R = (100 × Ttask) / Tplay R: CPU load [%]
Ttask: From playback start to playback end
Total amount of PCM_Task processing time
Tplay: Playback time