diff --git a/connectcore-demo-example/demoserver.py b/connectcore-demo-example/demoserver.py
index 8c3570f..6132766 100755
--- a/connectcore-demo-example/demoserver.py
+++ b/connectcore-demo-example/demoserver.py
@@ -790,7 +790,7 @@ def get_video_resolution():
         res = read_file("/sys/class/drm/card0/card0-DPI-1/modes")
     if res == NOT_AVAILABLE:
         res = read_file("/sys/class/graphics/fb0/modes")
-    if res == NOT_AVAILABLE:
+    if res == NOT_AVAILABLE or not res:
         return "No video device found"
 
     line = res.splitlines()[0]