Hi,
In my environment, portaudio with MME support generates choppy sound for the suggestedOutputLatency of less that 60 ms. 70 ms seems to work. In this case, hostBufferCount=8 and hostBufferSizeFrams=480 if the sample rate is 48 kHz. So, total buffer length is 3840 samples. Therefore, the resulted latency is 80 ms.
interesting. I've now did some experiments with a self compiled portaudio with MME and WASAPI and both worked flawless on my machine with a suggestedLatency of 10ms. Perhaps this is dependend on the sound card used in the computer. The callbacks are called with framesPerBuffer of 480.
OSS implementation in cygwin 3.4.9 always uses the buffer size of 125 ms. So, even if hostBufferCount=2 (current value of portaidio with OSS support), the latency is 250 ms. This might not be acceptable for some applications.
I wouldn't mind using OSS if it supports lower hostBufferSizes so that I don't get callbacks with a buffer size of 6000. Apparently suggestedLatency has no influence on that.
Unfortunately, OSS and MME/DSound/WASAPI can be exclusively enabled. I am currently considering whether to rollback portaudio to MME/ DSound/WASAPI until cygwin 3.5.0 is released.
I guess it would be possible but would probably require a patched configure script.
Either way if you change it away from OSS or now, I hope I could provide some useful feedback.
Best regards, Michael -- Problem reports: https://cygwin.com/problems.html FAQ: https://cygwin.com/faq/ Documentation: https://cygwin.com/docs.html Unsubscribe info: https://cygwin.com/ml/#unsubscribe-simple
