The buffer sizes in ffmpeg are more about ensuring that the calculated bitrate is accurate iirc than ensuring smooth streaming (although you need your bitrate enforced to guarantee smooth streaming).
IIRC (it's been a bit since I've configured this), you can specify both codec buffers and buffers for streaming to smooth out issues reading from the codec output. I could be wrong though.
Comments
The buffer sizes in ffmpeg are more about ensuring that the calculated bitrate is accurate iirc than ensuring smooth streaming (although you need your bitrate enforced to guarantee smooth streaming).
IIRC (it's been a bit since I've configured this), you can specify both codec buffers and buffers for streaming to smooth out issues reading from the codec output. I could be wrong though.