diff --git a/resources/templates/provision/grandstream/ht818/{$mac}.xml b/resources/templates/provision/grandstream/ht818/{$mac}.xml
index bd1bd54ca6..071d038cdf 100644
--- a/resources/templates/provision/grandstream/ht818/{$mac}.xml
+++ b/resources/templates/provision/grandstream/ht818/{$mac}.xml
@@ -1138,7 +1138,11 @@
     <!-- # FAX Mode. 0 - T.38 (Auto Detect), 1 - Pass Through -->
     <!-- # Number: 0, 1 -->
     <!-- # Mandatory -->
+    {if isset($grandstream_fax_mode)}
+    <P228>1</P228>
+    {else}
     <P228>0</P228>
+    {/if}
 
     <!-- # Re-INVITE After Fax Tone Detected. 0 - Disabled, 1 - Enabled. -->
     <!-- # Number: 0, 1 -->