diff --git a/playbooks/mpdf.yaml b/playbooks/mpdf.yaml
index 2887594..63a1cd5 100644
--- a/playbooks/mpdf.yaml
+++ b/playbooks/mpdf.yaml
@@ -36,7 +36,7 @@
     volume_normalization: no
     audio_buffer_size: 2048
     buffer_before_play: "1%"
-    backendhost: {{ inventory_hostname|replace("f", "b" ) }}
+    backendhost: "{{ inventory_hostname|replace("f", "b") }}"
       
   tasks:
     - name: Install mpdf on hosts