Comment 19 for bug 884705

Reading.
http://www.assembla.com/wiki/show/portaudio/BufferingLatencyAndTimingImplementationGuidelines
clarifies some points.

In "streamDetails->outputLatency", PA tries to report all latencies that are known. Unfortunately it does not only depend on the Sound API but also on the selected device. On my hardware PA reports 42 ms for ALSA + Intel sound card and 64 ms for ALSA + pulse, with the suggested Latency of 21 ms. In fact, the output latency is currently controlled by the buffer provided by Mixxx in this case.

So the patch from #12 is not a solution.

A flexible solution would be to allow the user to set the Buffer and the latency independent and report the current Latency in the GUI. This will offer optimum flexibility but will clutter the GUI and opens an other window for miss configuration.

The best solution for me, will be to set the buffer size in ms by user preferences and request a minimum latency. In this case PA will adopt this minimum possible Latency with this buffer. In fact, nothing will change compared to the current behavior except the wording.
"Latency" -> "Audio Buffer Size"

Additional we could report the current Latency in the preferences see Bug #884688.

What do you think?