Xenial Xerus has Audacious 3.6.2 which was released more than a year ago on May 30th, 2015. I would like to use the latest Audacious: 3.7.2 released on March 28th, 2016. How can I get the latest version?
You can add WebUpd8's PPA at https://launchpad.net/~nilarimogard/+archive/ubuntu/webupd8, which provides Audacious 3.7.2 (and plugins too) for Ubuntu 16.04:
sudo add-apt-repository ppa:nilarimogard/webupd8 sudo apt update sudo apt upgrade