diff --git a/tests/cmp_pcm.py b/tests/cmp_pcm.py
index e60f84e0a04986af130f7b7204bffa6efec576b2..d958327ccda7ddd9da99f0737133a3bcd9d8b4b2 100755
--- a/tests/cmp_pcm.py
+++ b/tests/cmp_pcm.py
@@ -44,7 +44,11 @@ def cmp_pcm(file1, file2, out_config, fs, get_mld=False, mld_lim=0, abs_tol=0) -
             f"file size in samples: file 1 = {s1.shape[0]},",
             f"file 2 = {s2.shape[0]}",
         )
-        return 1, "FAIL: File lengths differ"
+        reason = "FAIL: File lengths differ. MAXIMUM ABS DIFF: None"
+        if get_mld:
+            reason += " - MLD: None"
+
+        return 1, reason
 
     cmp_result = pyaudio3dtools.audioarray.compare(
         s1, s2, fs, per_frame=False, get_mld=get_mld