The most obvious audible change is if you are using software volume control and can take advantage of 32- or 24-bit DACs. Dithering can now occur on a 32-bit or 24-bit sample rather than on a 16-bit sample, making the noise floor very much lower. This is the case, for example, with a Pimoroni PHAT DAC.
+Here is the list of new features:
+
**New Features**
* 8-bit, 16-bit, 24-bit, 24-bit three-byte (S24_3LE and S24_3BE) and 32-bit output to ALSA devices. This will give audibly better results if you are using software volume control on a 24- or 32-bit-capable DAC. (Other back ends are not updated yet.)
* 44,100, 88,200, 176,400 and 352,800 sample per second output. This is done using simple upsampling. It's only worth doing if 44,100 samples per second output is not available.
* Internal processing including software volume control and interpolation is done after sample size and rate conversion.
* Apple ALAC decoder support. This needs the `libalac` library, available at [ALAC](https://github.com/mikebrady/alac). Add the flag `--with-apple-alac` to the `./configure` arguments. Then you can choose the Apple ALAC decoder in the configuration file. There is no obvious audible difference between this and the original decoder by David Hammerton.
* Support for `mbed TLS` has been added and the use of `PolarSSL` is deprecated, as `mbed TLS` is a development of `PolarSSL` and `PolarSSL` itself is not being developed further.
-* Settings that were denominated in frames are now deprecated but still honoured. Deprecation warnings are issued.
* Choose Network Interface. Add a new setting, for advanced users only, in the `general` section. Use the `interface` setting to allow you to specify the interface on which to provide the AirPlay service. Omit the setting to get the default, which is to choose the interfaces automatically.
* Set Max Volume. Add a new setting, for advanced users only, in the `general` section. Use the `volume_max_db` setting to allow you to specify the maximum level to set on the hardware mixer (if chosen) or the built-in software mixer otherwise. The software mixer's range is 0.0 dB to -96.1 dB. The setting must be a number with a decimal point, e.g. 21.3.
* An experimental new back end for `libsoundio`, a C library for cross-platform real-time audio input and output. Many thanks to [Serg Podtynnyi](https://github.com/shtirlic). Please see https://github.com/mikebrady/shairport-sync/pull/433 for more details.
----
* Processor load is up by about 10%.
* Settings have changed -- basically, any timings that were denominated in frames are now in seconds. Please refer to the shairport-sync.conf.sample file for details.
-* Sox-based interpolation at higher sample rates may overload your CPU -- yopu might have to choose between higher sample rates and sox-based interpolation.
+* Sox-based interpolation at higher sample rates may overload your CPU -- you might have to choose between higher sample rates and sox-based interpolation.
Version 3.0rc0 – Release Candidate 0