That's the approach I initially took, but experienced some combination of noticeable stuttering and latency regardless of which buffering strategy I tried... Had to switch to a shared memory ring buffer, along with some adaptive playback speed shenanigans (sometimes imperceptibly speeding up playback when falling behind production of audio samples, sometimes imperceptibly slowing down when there's less than a few milliseconds' worth of samples left in the ringbuffer), in order to achieve actually-gapless playback.