You need to "divide and conquer". I mean to find out where the tik tik tik gets into the system.
I assume you don't hear the sound if you're just recording the sound. But you need to find out if the tiks are getting in while recording or in playback
How? Well do you hear the tiks if playing back a known-perfect recording or a mathematically-generated sine-wave?
Another thing is to find out if they are analog or digital.
Analog:
The digital part does things in bursts. These take gulps from the power-supply. If your power supply arrangement doesn't adequately separate digital and analog sections, these gulps get onto the analog power lines and might be heard - either in what the recording part converts to digital or how the playback part converts to analog.
Digital:
The digital part takes finite time to read and write to/from SDIO. What happens to the audio during this time? Do you buffer it adequately, or is there a risk of missed or late samples?
You might be using a codec to compress / decompress the audio. This often works in blocks, and again takes finite time needing buffering. Also, if you don't retain the codec state properly from one block to the next, there will be a tik between blocks.
Hope this helps,
Danish
