UAUDIO_BUFFER_MS_MAX
if (val > UAUDIO_BUFFER_MS_MAX)
val = UAUDIO_BUFFER_MS_MAX;
if (ms > UAUDIO_BUFFER_MS_MAX)
ms = UAUDIO_BUFFER_MS_MAX;
howmany(chan_alt->sample_rate * UAUDIO_BUFFER_MS_MAX, 1000);