[pulseaudio-discuss] Single char silence with Orca and pulseaudio

[Bill Cox]

Hi.

I'm trying to debug a problem in Ubuntu Lucid that appears to be
pulseaudio related.  When we set the speech rate of espeak to 100% in
Orca, and enable key echo, the keys are not announced when pressed.
Instead, when you type one key, no sound is played, but when you press
another key, both keys are played.

I've traced this bug from Espeak to libao and now to pulseaudio.
Libao is using the pa_simple_write function to play speech sounds.  I
find that when sounds of over about 2000 samples are sent, then then
sound is played.  If sounds of less than 2000 samples are sent, then
they are not played, and instead buffered somewhere until the next
sample is passed to pa_simple_write.

Would anyone have any idea of what might be causing this, or what area
I should inspect more closely?  Currently, I'm using fprintf commands
to trace the pulseaudio source.  So far, I've traced this from
simple.c to stream.c to pstream.c, where I see the samples being
queued.  From there, I'm a bit lost about how the samples are moved
along.

Thanks,
Bill