diff --git a/plugins/voip/zapchans b/plugins/voip/zapchans
index c0304f72..bf2a41cb 100755
--- a/plugins/voip/zapchans
+++ b/plugins/voip/zapchans
@@ -47,6 +47,6 @@ fi
 # cron, and dumps its output to a separate file for this plugin to read later on. Letting
 # Munin plugins run as root is a security hole.
 
-zap=`asterisk -rx 'zap show channels' |grep -v "[[:digit:]]*[[:space:]] local" |grep -vc "Chan Extension"`
+zap=$(asterisk -rx 'zap show channels' |grep -v "[[:digit:]]*[[:space:]] local" |grep -vc "Chan Extension")
 
 echo "calls.value $zap"