Bring over some updates that were applied to the master branch.

diff --cc .gitignore
Simple merge

diff --cc BUILDFORAP1.md
index 6941e564eb8d1e91477803984489e9e37d89d989,85a2445152cc222d7645bbb5445b31386522c7ce..847346ba460612fba9ed9c576bf45f19679ffc73
--- 1/BUILDFORAP1.md
--- 2/INSTALL.md
+++ b/BUILDFORAP1.md
@@@ -17,9 -17,9 +17,9 @@@ If you are using WiFi, you should turn 
  ```
  # iwconfig wlan0 power off
  ```
- WiFi Power Management will put the WiFi system in low-power mode when the WiFi system considered inactive, and in this mode it may not respond to events initiated from the network, such as AirPlay requests. Hence, WiFi Power Management should be turned off. (See [TROUBLESHOOTING.md](https://github.com/mikebrady/shairport-sync/blob/master/TROUBLESHOOTING.md#wifi-adapter-running-in-power-saving--low-power-mode) for more details.)
+ WiFi Power Management will put the WiFi system in low-power mode when the WiFi system is considered inactive, and in this mode it may not respond to events initiated from the network, such as AirPlay requests. Hence, WiFi Power Management should be turned off. (See [TROUBLESHOOTING.md](https://github.com/mikebrady/shairport-sync/blob/master/TROUBLESHOOTING.md#wifi-adapter-running-in-power-saving--low-power-mode) for more details.)
  
 -Reboot the Pi.
 +Reboot the computer.
  
  ### Remove Old Copies
  Before you begin building Shairport Sync, it's best to search for and remove any existing copies of the application, called `shairport-sync`. Use the command `$ which shairport-sync` to find them. For example, if `shairport-sync` has been installed previously, this might happen:

diff --cc CAR INSTALL.md
Simple merge

diff --cc FEDORA.md
index cf8cbc5078749f5961a3065a5274381af290ef41,7690dbd6dd77db4c5de4f718379190f977316c66..f105ddbe539a4efcb3df7688f8a3c6c7f4de4185
--- 1/FEDORA.md
--- 2/FEDORA.md
+++ b/FEDORA.md
@@@ -1,6 -1,9 +1,9 @@@
 -Fedora Installation Guide
 +Fedora Installation Guide [Needs updating for Airplay 2]
  -----
- 
+ Update everything...
+ ```
+ # yum update
+ ```
  Install the toolchain and pre-requisites, if necessary:
  ```
  # yum install make automake gcc gcc-c++ kernel-devel

diff --cc OPENBSD.md
index 6b18f97918c61ec5831dffa5a3633eaff1906b81,16465e6b0eecbd32c404c21b4c869743d2bd4ca4..c046390d1e1957a53ac29d7c01292f30821fb1e1
--- 1/OPENBSD.md
--- 2/OPENBSD.md
+++ b/OPENBSD.md
@@@ -1,6 -1,6 +1,6 @@@
 -Shairport Sync on OpenBSD
 +Shairport Sync on OpenBSD [AirPlay 2 Not Supported]
  ----
- This is an initial note about installing Shairport Sync on OpenBSD. Shairport Sync compiles and runs natively on OpenBSD using the `sndio` back end.
+ This is a note about installing Shairport Sync on OpenBSD. Shairport Sync compiles and runs natively on OpenBSD using the `sndio` back end. For general information on `sndio` please follow [this link](http://www.sndio.org).
  
  Unlike FreeBSD, it seems that OpenBSD does not use the directory `/usr/local/etc` as a system configuration directory ("`sysconfdir`") but follows the same practice as Linux in using `/etc` as the default `sysconfdir`.
  

diff --cc UPDATING.md
index 73e18fb079be5da283992e06f9722f9e06702c43,6988528518d153174da49ef3231dbba8da17023c..cbfdc635968aef7dc5d6107b6bb9c85e89ab760a
--- 1/UPDATING.md
--- 2/UPDATING.md
+++ b/UPDATING.md
@@@ -1,6 -1,6 +1,8 @@@
  
 -### Updating Shairport Sync
 -This guide is for building and updating an installation of Shairport Sync. If you wish to build an installation of Shairport Sync to replace an installation that came from a package, this doesn't really apply – instead, please follow the guide at [INSTALL.md](https://github.com/mikebrady/shairport-sync/blob/master/INSTALL.md).
 +### Updating Shairport Sync [Needs updating for Airplay 2]
- This guide is for updating an installation of Shairport Sync. If you installed Shairport Sync from a package, most of these instructions don't apply – please go to the section at the end called "Post Update Tasks"
++This guide is for building and updating an installation of Shairport Sync.
++
++If you updated Shairport Sync from a package, most of these instructions don't apply – please go to the section at the end called "Post Update Tasks". If you wish to build an installation of Shairport Sync to replace an installation that came from a package, instructions don't apply either – instead, please follow the guide at [INSTALL.md](https://github.com/mikebrady/shairport-sync/blob/master/INSTALL.md).
  
  To do an update, you basically have to go through the whole process of building Shairport Sync again,
  but a few steps are shorter because you've done them before; you won't have to reinstall the build tools or libraries needed, and you won't have to define the user and group or reconfigure the settings in the configuration file.

diff --cc audio_alsa.c
index ed4f3c88c66fed97447e4652fea607185063b96f,b464279c2e1e6fdfd67909c5288b5031d79213a3..4aa6ee9b881ddbe0b3236e552cc10e6fc862dcf9
--- 1/audio_alsa.c
--- 2/audio_alsa.c
+++ b/audio_alsa.c
@@@ -1,7 -1,7 +1,7 @@@
  /*
   * libalsa output driver. This file is part of Shairport.
   * Copyright (c) Muffinman, Skaman 2013
-- * Copyright (c) Mike Brady 2014 -- 2019
++ * Copyright (c) Mike Brady 2014 -- 2021
   * All rights reserved.
   *
   * Permission is hereby granted, free of charge, to any person