I have a simple program that captures audio from an audio device. I have configured a nominal sample rate of 48000Hz and a buffer size of 1 millisecond. The audio sub system should execute my capture code with approximately 1000Hz.
My assumption is that the audio clock (LRCLK) is not running at exactly 48000Hz. Using this 1kHz-callback from the audio system I want to approximate the actual sampling frequency relativ to another clock. Currently I use the system clock of my workstation as a reference. I plan to use a network clock.
For my very first experiment I used a simple moving average with a period of 1000 but there is still very much jitter. Sometimes the average jumps by 2Hz which seems much to me.
What is the proper way to go here?
Many thanks!