diff --git a/bin/import_swc.py b/bin/import_swc.py
index fb4a8d80..6b9273cf 100755
--- a/bin/import_swc.py
+++ b/bin/import_swc.py
@@ -214,7 +214,7 @@ def collect_samples(base_dir, language):
             elif duration > CLI_ARGS.max_duration > 0 and CLI_ARGS.ignore_too_long:
                 skip = True
                 p_reason = 'exceeded duration'
-            elif int(duration / 20) < len(text):
+            elif int(duration / 30) < len(text):
                 skip = True
                 p_reason = 'too short to decode'
             elif duration / len(text) < 10:
diff --git a/bin/import_tuda.py b/bin/import_tuda.py
index 28e09beb..89590144 100755
--- a/bin/import_tuda.py
+++ b/bin/import_tuda.py
@@ -76,7 +76,7 @@ def check_wav_file(wav_path, sentence):  # pylint: disable=too-many-return-state
             return False, 'wrong number of channels'
         if sample_width != SAMPLE_WIDTH:
             return False, 'wrong sample width'
-        if milliseconds / len(sentence) < 20:
+        if milliseconds / len(sentence) < 30:
             return False, 'too short'
         if milliseconds > CLI_ARGS.max_duration > 0:
             return False, 'too long'