Mumble

Mumble is low-latency, high-quality voice communication for gamers. Includes game linking, so voice from other players comes from the direction of their characters, and has echo cancellation so the sound from your loudspeakers won't be audible to other players. It is open source software released under the BDS license.

• For binary packages distributed by the Mumble team, OpenSSL has been updated to 1.0.0n due to OpenSSL Security Advisory [06 August 2014]
• A PulseAudio issue that could cause the Mumble client to crash on launch has been fixed.
• Various source-level issues that made the Mumble build fail when built with Clang has been fixed.