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+Version 3.3d39 to Version 3.3d28
+====
+
+**New Feature**
+
+This important new feature helps with removing some annoying clicking / popping noises. It is really pretty impressive, especially combined with the fixes to the dithering code described below. If you can enable 24- or 32-bit audio output to your output device, you can get even better results.
+
+This is an ALSA-specific attempt to remove the annoying low-level clicking sounds that some output devices make just when they start processing audio and somethines when they stop. Typically a faint click might be heard just before a play session starts or just before audio resumes after a pause. Similarly, a faint click can sometimes be heard just after a play session ends.
+
+It is extremely difficuly to remove these clicks completely from the hardware, so this new feature ensures that — once Shairport Sync has started — the output device avoids situations where these clicks might be generated by *always* playing audio. To accomplish this, if Shairport Sync isn't actually playing anything, audio frames consisting of silence are sent to the output device. Apart from the initial startup transition, the output device never stops playing, avoiding both starting and stopping transitions.
+
+To enable this feature, a new `alsa` group setting with the name `disable_standby_mode` is available. (If you do a full `$ sudo make install`, a new sample configuration file with this setting in it is installed at `/etc/shairport-sync.conf.sample` or `/usr/local/etc/shairport-sync.conf.sample`.) The default for the setting is `"no"`.
+
+A downside to this feature is that the output device totally dedicated to Shairport Sync. For this reason, this new feature is disabled by default. 
+
+Note -- this setting is likely to change. It will probably be necessary to modify it somehow to enable it to be used in integrated systems. Your feedback would be welcome.
+
+**Enhanccements and Bug Fixes**
+
+At present, Shairport Sync adds dither to the audio if (a) the built-in software-based volume control is used, (b) if the audio is mixed to mono or (3) if there is a change in sample size, say from 16- to 24-bit. The code for generating dither has been much improved. Due to a poor pseudo-random number arrangement, the dither noise didn't sound like white noise -- now it does.
+
+In addition, if dither is to be added, it is also added to the silence inserted just prior to the start of play, and is also added tthe silent frames used to prevent the output device from going into standby mode, if selected.
+
 Version 3.3d37 to Version 3.3d22
 ====