diff --git a/patacrep/latex/__init__.py b/patacrep/latex/__init__.py
index 5ea81a67..83d12906 100644
--- a/patacrep/latex/__init__.py
+++ b/patacrep/latex/__init__.py
@@ -130,5 +130,5 @@ def lang2babel(lang):
     try:
         return BABEL_LANGUAGES[checklanguage(lang)]
     except UnknownLanguage as error:
-        LOGGER.error(str(error))
+        LOGGER.warning(str(error))
         return BABEL_LANGUAGES[error.fallback]
diff --git a/patacrep/latex/lexer.py b/patacrep/latex/lexer.py
index f76500f8..0e60e826 100644
--- a/patacrep/latex/lexer.py
+++ b/patacrep/latex/lexer.py
@@ -72,7 +72,7 @@ class SimpleLexer:
     @staticmethod
     def t_error(token):
         """Manage errors"""
-        LOGGER.error("Illegal character '{}'".format(token.value[0]))
+        LOGGER.warning("Illegal character '{}'".format(token.value[0]))
         token.lexer.skip(1)
 
 class SongLexer(SimpleLexer):
diff --git a/patacrep/songs/chordpro/lexer.py b/patacrep/songs/chordpro/lexer.py
index 16f494b3..ab8d4de6 100644
--- a/patacrep/songs/chordpro/lexer.py
+++ b/patacrep/songs/chordpro/lexer.py
@@ -142,7 +142,7 @@ class ChordProLexer:
             )
         if self.filename is not None:
             message = "File {}: {}".format(self.filename, message)
-        LOGGER.error(message)
+        LOGGER.warning(message)
         token.lexer.skip(1)
 
     def t_error(self, token):
diff --git a/patacrep/songs/syntax.py b/patacrep/songs/syntax.py
index d3b5c0ac..0ea5208b 100644
--- a/patacrep/songs/syntax.py
+++ b/patacrep/songs/syntax.py
@@ -45,9 +45,9 @@ class Parser:
         else:
             text += "."
         if self.filename is None:
-            LOGGER.error(text)
+            LOGGER.warning(text)
         else:
-            LOGGER.error("File {}: {}".format(self.filename, text))
+            LOGGER.warning("File {}: {}".format(self.filename, text))
 
     def p_error(self, token):
         """Manage parsing errors."""