diff --git a/README.md b/README.md
index b2137f9..c32e800 100644
--- a/README.md
+++ b/README.md
@@ -77,7 +77,8 @@ See also [Friends of Rust](https://www.rust-lang.org/friends.html) (organization
   * [tailhook/vagga](https://github.com/tailhook/vagga) — a containerization tool without daemons [<img src="https://travis-ci.org/tailhook/vagga.svg?branch=master">](https://travis-ci.org/tailhook/vagga)
 * [cristianoliveira/funzzy](https://github.com/cristianoliveira/funzzy) — a configurable watcher inspired in [entr](http://entrproject.org/) [<img src="https://api.travis-ci.org/cristianoliveira/funzzy.svg?branch=master">](https://travis-ci.org/cristianoliveira/funzzy)
 
-
+* **Audio**
+  * [indiscipline/zrtstr](https://github.com/indiscipline/zrtstr) — a command line utility for checking if stereo wav files are faux-stereo (i.e. have identical channels) and converting such files to mono. [<img src="https://travis-ci.org/indiscipline/zrtstr.svg?branch=master">](https://travis-ci.org/indiscipline/zrtstr)
 * **Database**
   * [pingcap/tikv](https://github.com/pingcap/tikv) — a distributed KV database in Rust [<img src="https://travis-ci.org/pingcap/tikv.svg?branch=master">](https://travis-ci.org/pingcap/tikv)
   * [seppo0010/rsedis](https://github.com/seppo0010/rsedis) — a Redis reimplementation in Rust [<img src="https://travis-ci.org/seppo0010/rsedis.svg?branch=master">](https://travis-ci.org/seppo0010/rsedis)