Need to set prebuf to 1 in pulse.c

[Bill Cox]

A Vinux user who listens to espeak at high speed has found another
problem.  To reproduce it, in Orca preferences, set the synth to
espeak, and speed to 100%.  Then run gedit.  Type a bunch of 'e'
characters.  Then, use the arrow keys to listen to them.  When you
arrow over an 'e', it's not spoken, until you arrow over another one.

I found that setting prebuf to 1, rather than the default of -1, that
the problem goes away on my machine.  I'll put this in the Vinux
testing repository for a bit to see if it causes any problems.  The
change is just one line:

diff -Naur opentts-0.1/src/audio/pulse.c opentts-0.1.build/src/audio/pulse.c
--- opentts-0.1/src/audio/pulse.c       2010-06-17 15:57:08.992708521 -0400
+++ opentts-0.1.build/src/audio/pulse.c 2010-06-18 06:37:04.339057440 -0400
@@ -172,7 +172,7 @@
                buffAttr.maxlength = (uint32_t) - 1;
                //buffAttr.tlength = (uint32_t)-1; - this is the default, which
causes key echo to not work properly.
                buffAttr.tlength = pulse_id->pa_min_audio_length;
-               buffAttr.prebuf = (uint32_t) - 1;
+               buffAttr.prebuf = 1;
                buffAttr.minreq = (uint32_t) - 1;
                buffAttr.fragsize = (uint32_t) - 1;