diff --git a/allocator.py b/allocator.py
index 43b3063..c3cd8ec 100644
--- a/allocator.py
+++ b/allocator.py
@@ -1,5 +1,4 @@
 # memory manager to prevent redundant calls to files and save up disk usage
-# may cause massive ram usage if we input too many pck at once, fix required
 import os
 import mmap
 
@@ -10,13 +9,14 @@ class Allocator:
 	def load_file(self, path):
 		filename = os.path.basename(path)
 		with open(path, "r+b") as f:
-			mmap_object = mmap.mmap(f.fileno(), 0)
-
-		self.files[filename] = mmap_object,
+			mmap_object = mmap.mmap(f.fileno(), 0, access=mmap.ACCESS_READ)
 
+		self.files[filename] = mmap_object
 
 	def read_at(self, file, offset, size):
-		data = self.files[file][offset:offset+size]
+		mmap_object = self.files[file]
+		mmap_object.seek(offset)
+		data = mmap_object.read(size)
 		return data
 
 	def free_mem(self):
diff --git a/app.py b/app.py
index cf810bf..ef41b01 100644
--- a/app.py
+++ b/app.py
@@ -221,6 +221,7 @@ class AnimeWwise(QMainWindow):
 	# misc
 	def resetApp(self):
 		self.resetTreeWidget()
+		self.extract.reset()
 		self.tabs.setTabEnabled(0, True)
 		self.tabs.setTabEnabled(1, False)
 		self.tabs.setTabEnabled(2, False)
diff --git a/extract.py b/extract.py
index d8b72b1..f08de4b 100644
--- a/extract.py
+++ b/extract.py
@@ -14,7 +14,6 @@ from allocator import Allocator
 cwd = os.getcwd()
 path = lambda path: os.path.join(cwd, path)
 call = lambda args: subprocess.call(args, stdout=subprocess.DEVNULL, stderr=subprocess.STDOUT)
-allocator = Allocator()
 
 skips = "000000000" # used for debugging
 
@@ -40,6 +39,8 @@ class WwiseExtract:
 			"temp": tempfile.TemporaryDirectory()
 		}
 
+		self.allocator = Allocator()
+
 		# self.progress = progress
 
 	def path(self, base, path):
@@ -374,3 +375,9 @@ class WwiseExtract:
 		# allocator.load_file(os.path.join(_input, "2050.pck"))
 		# allocator.read_at("2050.pck", 0, 0)
 		pass
+	### other ###
+
+	def reset(self):
+		if self.mapper is not None:
+			self.mapper.reset()
+		self.allocator.free_mem()
diff --git a/gui.ui b/gui.ui
index e08efea..9f2c4b7 100644
--- a/gui.ui
+++ b/gui.ui
@@ -152,7 +152,7 @@
          <item row="0" column="0">
           <widget class="QLabel" name="assetMapLabel">
            <property name="text">
-            <string>Asset map (optional)</string>
+            <string>Asset map</string>
            </property>
           </widget>
          </item>
diff --git a/mapper.py b/mapper.py
index b4cc759..0fe3d9b 100644
--- a/mapper.py
+++ b/mapper.py
@@ -166,3 +166,9 @@ class Mapper:
 			data.append(self.langs_offsets[int.from_bytes(key_data[:1], "little")])
 
 		return data
+
+	def reset(self):
+		self.reader = None
+		self.langs_offsets.clear()
+		self.files_offsets.clear()
+		self.keys_data.clear()