diff --git a/jubeatools/formats/jubeat_analyser/memo2/load.py b/jubeatools/formats/jubeat_analyser/memo2/load.py
index 47d364d..3c817b3 100644
--- a/jubeatools/formats/jubeat_analyser/memo2/load.py
+++ b/jubeatools/formats/jubeat_analyser/memo2/load.py
@@ -205,8 +205,6 @@ class Memo2Parser(JubeatAnalyserParser):
                 "offset increase command (r=...)  found outside of the file "
                 "header, this is not supported by jubeatools"
             )
-        elif self.offset is None:
-            super().do_o(value)
         else:
             super().do_r(value)
 
@@ -264,13 +262,7 @@ class Memo2Parser(JubeatAnalyserParser):
                             "Chart contains a pause that's not happening at the "
                             "very first beat, these are not supported by jubeatools"
                         )
-                    if self.offset is None:
-                        self.offset = event.duration
-                    else:
-                        # This could happen if several pauses exist at the first
-                        # beat of the chart or if both an in-bar pause and an
-                        # o=... command exist
-                        self.offset += event.duration
+                    self.offset += event.duration
 
             bar_notes = [e for e in bar if isinstance(e, str)]
             line = Memo2ChartLine(raw_line.position, bar_notes)
diff --git a/jubeatools/formats/memon/test_memon.py b/jubeatools/formats/memon/test_memon.py
index bb1c55c..8679abb 100644
--- a/jubeatools/formats/memon/test_memon.py
+++ b/jubeatools/formats/memon/test_memon.py
@@ -30,7 +30,7 @@ def dump_and_load(
         filename, contents = list(files.items())[0]
         file.write(contents)
         file.seek(0)
-        actual_song = load_function(file.name)
+        actual_song = load_function(Path(file.name))
 
     assert expected_song == actual_song
 
diff --git a/jubeatools/formats/typing.py b/jubeatools/formats/typing.py
index 0047fb7..2ebfeb9 100644
--- a/jubeatools/formats/typing.py
+++ b/jubeatools/formats/typing.py
@@ -1,7 +1,6 @@
+from pathlib import Path
 from typing import Any, Callable, Dict, Protocol
 
-from path import Path
-
 from jubeatools.song import Song
 
 
diff --git a/jubeatools/testutils/strategies.py b/jubeatools/testutils/strategies.py
index 9c555a4..7252a92 100644
--- a/jubeatools/testutils/strategies.py
+++ b/jubeatools/testutils/strategies.py
@@ -4,7 +4,7 @@ Hypothesis strategies to generate notes and charts
 from decimal import Decimal
 from enum import Enum, Flag, auto
 from itertools import product
-from typing import Any, Callable, List, Optional, Set, TypeVar, Union
+from typing import Any, Callable, Dict, List, Optional, Set, TypeVar, Union
 
 import hypothesis.strategies as st
 from multidict import MultiDict
@@ -118,7 +118,9 @@ def notes(draw: DrawFunc, options: NoteOption) -> Set[Union[TapNote, LongNote]]:
     if NoteOption.COLLISIONS in options:
         return raw_notes
     else:
-        last_notes = {NotePosition(x, y): None for y, x in product(range(4), range(4))}
+        last_notes: Dict[NotePosition, Optional[BeatsTime]] = {
+            NotePosition(x, y): None for y, x in product(range(4), range(4))
+        }
         notes: Set[Union[TapNote, LongNote]] = set()
         for note in sorted(raw_notes, key=lambda n: (n.time, n.position)):
             last_note_time = last_notes[note.position]
diff --git a/mypy.ini b/mypy.ini
index 9d1de39..2699243 100644
--- a/mypy.ini
+++ b/mypy.ini
@@ -1,11 +1,20 @@
 [mypy]
-#disallow_untyped_calls = True
+disallow_untyped_calls = True
 disallow_untyped_defs = True
 disallow_incomplete_defs = True
 check_untyped_defs = True
-#disallow_untyped_decorator = True
+#disallow_untyped_decorators = True
 no_implicit_optional = True
+warn_redundant_casts = True
 warn_unused_ignores = True
 warn_return_any = True
-warn_redundant_casts = True
+warn_unreachable = True
+
+[mypy-constraint]
+ignore_missing_imports = True
+
+[mypy-parsimonious.*]
+ignore_missing_imports = True
+
+[mypy-sortedcontainers]
 ignore_missing_imports = True
\ No newline at end of file