VLC Media Player - VLC is a free and open source cross-platform multimedia player and framework.
ScreenCloud - ScreenCloud is a simple, cloud-based Digital Signage software solution that makes it easy to display video, images and content on screens.
AIMP - AIMP : Free Audio Player : Официальный сайт программы
Embed Signage - Multi-platform Digital Signage Software that's quick to learn and powerful to use. Packed with features, simple to use and wide range of device platform support. A better way to manage your Digital Signage.
foobar2000 - An advanced freeware audio player for the Windows platform.
PDComms Tool - Digital Signage