diff --git a/srcpkgs/jack/patches/fix-narrowing.patch b/srcpkgs/jack/patches/fix-narrowing.patch
new file mode 100644
index 0000000000..ae98ba6f43
--- /dev/null
+++ b/srcpkgs/jack/patches/fix-narrowing.patch
@@ -0,0 +1,22 @@
+Fix for gcc6 -Wnarrowing error.
+
+--- tests/iodelay.cpp	2014-07-18 14:28:13.000000000 +0200
++++ tests/iodelay.cpp	2016-09-11 18:12:00.563013354 +0200
+@@ -167,8 +167,8 @@
+ static jack_port_t    *jack_capt;
+ static jack_port_t    *jack_play;
+ 
+-jack_latency_range_t   capture_latency = {-1, -1};
+-jack_latency_range_t   playback_latency = {-1, -1};
++jack_latency_range_t   capture_latency = {(jack_nframes_t)-1, (jack_nframes_t)-1};
++jack_latency_range_t   playback_latency = {(jack_nframes_t)-1, (jack_nframes_t)-1};
+ 
+ void
+ latency_cb (jack_latency_callback_mode_t mode, void *arg)
+@@ -266,4 +266,4 @@
+     return 0;
+ }
+ 
+-// --------------------------------------------------------------------------------
+\ Kein Zeilenumbruch am Dateiende.
++// --------------------------------------------------------------------------------
diff --git a/srcpkgs/jack/template b/srcpkgs/jack/template
index 3ed42e30d3..f0ad8ac8aa 100644
--- a/srcpkgs/jack/template
+++ b/srcpkgs/jack/template
@@ -1,7 +1,7 @@
 # Template file for 'jack'
 pkgname=jack
 version=1.9.10
-revision=9
+revision=10
 # XXX libffado (firewire)
 hostmakedepends="pkg-config python"
 makedepends="eigen opus-devel libsamplerate-devel readline-devel dbus-devel celt-devel"