Capture buffer size doesn't affect latency

[okaniku]

I have an 'echo' app that captures my mic and plays it back immediately. I'm trying to improve the latency. I'm able to noticeably improve the latency by increasing the capture frequency. I expected to also be able to improve the latency by decreasing the buffer size (i.e. the bufferSize parameter on alcCaptureOpenDevice), but this doesn't happen.

Is this a known issue, or is my assumption incorrect?

[kcat]

The capture buffer size specifies the minimum total buffer that captured samples are read into. It doesn't affect how long it takes for samples coming in to be ready for reading, only how long you can wait before you start losing samples from a buffer overrun.

There currently isn't a way to specify the period or packet size, which would determines how many samples need to be captured before the app is made aware of them.