diff --git a/fuzzers/014-ffsrcemux/top.py b/fuzzers/014-ffsrcemux/top.py
index 398faf4f..dea5afb8 100644
--- a/fuzzers/014-ffsrcemux/top.py
+++ b/fuzzers/014-ffsrcemux/top.py
@@ -9,8 +9,8 @@ print('//Requested CLBs: %s' % str(CLBN))
 
 
 def gen_slices():
-    for _tile_name, site_name, _site_type in util.gen_sites(['SLICEL',
-                                                             'SLICEM']):
+    for _tile_name, site_name, _site_type in util.get_roi().gen_sites(
+        ['SLICEL', 'SLICEM']):
         yield site_name