All these bugs and "no sound output" complaints with Pulseaudio bring back the 
idea of finding a way to make Jack replace Pulseaudio altogether. Removing 
pulseaudio is not always enough, in many but not all cases a replacement is 
needed. I remember the old days of Dapper and applications grabbing the sound 
card and having to reboot just to get audacity to connect to alsa, and as late 
as Hardy using sound cards that would only connect to one program at a time. 
This while all those Windows clunkers made that one program a sound server that 
seemed to work fine. We have  a good sound server too, jack, and a good front 
end for it, qjackctl, which I discovered in ubuntustudio hardy.

 My big desktops do fine with straight ALSA for my video editing(kdenlive) , 
audio editing(audacity) and general uses. Their onboard sound cards include 
mixer functions enough to play sound from multiple sources with alsa by itself. 
This is apparently a hardware support capability.  My intel Atom netbook, 
containing a copy of the same OS, is another story entirely. No output from any 
mono soundtrack in alsa, as the soundcard does not support a mono output at 
all. On the other hand, pulseaudio is just too heavy for it, killing sync in 
video playback, even for 360p h264 video.

I ended up using jack as a pulseaudio replacement in that netbook. Anything 
other than flash or audacity, I fire up jack from qjackctl.

Using no sound server, only Flash, Xine, kdenlive and audacity can connect to 
alsa directly on that sound card. With jack, all the video players and 
audacious work fine, Mplayer and Audacious needing to be told in preferences to 
use jack.   Using either jack for sound or straight alsa(xine only) with a 
stereo soundtrack, that same netbook will only fall 1 or 2 seconds behind the 
sound and sometimes keep up entirely on a 720p HD video at 25 fps in H264 
codec. A full 30fps still defeats it. This shows that Jack is much lighter and 
more efficient code than pulseaudio. In fact, it shows that Jack is imposing 
very little load on the CPU compared to no sound server at all. I learned about 
Pulsaudio's resource use playing with old Pentium 3's, when Lucid could not 
play video files that Jaunty played just fine. Removing pulseaudio restored the 
playback sync.

Thanks to whoever put on onto using Volti to control volume with alsa direct or 
via jack! That takes care of the "no volume control applet without pulseaudio" 
issue and works in most DE's. You need the classic-systray extension to put it 
where you can see it in gnome-shell, comes up fine in both Icewm(traditional 
system tray) and in Unity if you add it to the whitelist for systray applets. 

Audacity works fine with Jack running, the only showstoppers for running jack 
full-time by itself are kdenlive (no Jack support yet!) and that old binary 
blob nasty, Adobe Flash. I am using 64 bit flash direct from Adobe, I do  know 
if the "pulseaudio-extrasound" package aimed at making Pulseaudio work would 
work with jack instead. With adobe deciding to throw Firefox under the bus and 
push proprietary browsers, I have a feeling open-source replacements for flash 
are about to hit the big time anyway.

Three ways of making Flash work with Jack  via alsa, gstreamer, or pulseaudio,  
plus a library for direct Jack support for Flash was being described at 

http://jackaudio.org/routing_flash

This page dates back to 2012. All these methods are said to create some added 
latency in audio from Flash, opposite the audio ahead of video effect that a 
too-heavy CPU load or slow graphics will create. Have yet to test them, I 
control jack from qjackctl on the netbook-and rarely use Flash to actually 
watch videos, as I download and keep anything worth watching anyway due to 
limited bandwidth and a preference for local copies of everything.

None of that matters on a big, high-powered A/V worstation, though a direct 
jack/no pulseaudio solution might help with other kinds of latency issues. What 
does matter is getting sound to work on a sound editing system without forcing 
users to learn a lot of new programming that might send them to another distro.

Having to start qjackctl or configure an application in its preferences to use 
Jack is one thing, having to root around on Google for what text file to exit, 
commands to run, etc is quite another.

With Precise now out, this question can again be considered for future 
reference. Thankfully, in Linux distros nobody has to wait, if Pulseaudio 
doesn't work for a user it can be removed and Ubuntu has been careful to keep 
too much from depending on it.  

Maybe a debian package that conflicts with pulseaudio, depends on jack and 
qjackctl, pulls in one of the solutions for flash and anto-configures other 
applications to use Jack by default would make this something an end user could 
actually work with?  That would be something that could be used as an advanced 
option at install or a recommended fix for situations where Pulseaudio acts up.



                                          
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