diff --git a/lib/setup/destination b/lib/setup/destination
index 7293fbf..c67c63d 100644
--- a/lib/setup/destination
+++ b/lib/setup/destination
@@ -451,7 +451,6 @@ setupDestination() {
 			echo "Invalid frequency value: $value" >&2
 			comeagain
 		fi
-		unset expr
 	}
 	comeagain
 	if [ -n "${destinationfrequency["$destination"]}" ] \
@@ -492,4 +491,5 @@ setupDestination() {
 	fi
 	destinationmaxbps[$destination]="$value"
 	unset regen
+	unset expr
 }