diff --git a/bundles/voc-loudness-monitor/items.py b/bundles/voc-loudness-monitor/items.py
index aab12ba..1e611b7 100644
--- a/bundles/voc-loudness-monitor/items.py
+++ b/bundles/voc-loudness-monitor/items.py
@@ -34,6 +34,10 @@ streams = {
 files = {}
 svc_systemd = {}
 
+pkg_apt = {
+    'ffmpeg': {},
+}
+
 for stream_id, config in streams.items():
     config['id'] = stream_id
 
@@ -45,6 +49,9 @@ for stream_id, config in streams.items():
         'triggers': {
             'svc_systemd:loudness_{}:restart'.format(stream_id),
         },
+        'needs': {
+            'pkg_apt:ffmpeg',
+        },
     }
     files['/etc/systemd/system/loudness_{}.service'.format(stream_id)] = {
         'source': 'loudness.service',