diff --git a/files/scripts/install-xpadneo.sh b/files/scripts/install-xpadneo.sh
index 0994751..a6c8930 100644
--- a/files/scripts/install-xpadneo.sh
+++ b/files/scripts/install-xpadneo.sh
@@ -4,11 +4,11 @@
 set -oue pipefail
 
 echo "INFO: grab kernel module"
-KERNEL_VER=${ls /lib/modules | head -n 1}
+KERNEL_VER=$(ls /lib/modules | head -n 1)
 echo $KERNEL_VER
 
 echo "INFO: grab xpad modules"
-MODULE_VER=${ls /usr/src | grep xpadneo |  sed 's/-/\//'}
+MODULE_VER=$(ls /usr/src | grep xpadneo |  sed 's/-/\//')
 echo $MODULE_VER
 
 echo "INFO: build and install xpadneo"