diff --git a/CITATION.cff b/CITATION.cff
index b6662d027..b6d4afcd1 100644
--- a/CITATION.cff
+++ b/CITATION.cff
@@ -41,7 +41,7 @@ authors:
 
 date-released: 2023-03-23
 doi: 10.5281/zenodo.7869553
-version: "1.1.0"
+version: "1.1.1"
 repository-code: "git@github.com:EIT-ALIVE/eitprocessing"
 keywords:
   - Mechanical lung ventilation
diff --git a/eitprocessing/__init__.py b/eitprocessing/__init__.py
index 6849410aa..a82b376d2 100644
--- a/eitprocessing/__init__.py
+++ b/eitprocessing/__init__.py
@@ -1 +1 @@
-__version__ = "1.1.0"
+__version__ = "1.1.1"
diff --git a/eitprocessing/datahandling/continuousdata.py b/eitprocessing/datahandling/continuousdata.py
index f6b0e7a3e..8aec492de 100644
--- a/eitprocessing/datahandling/continuousdata.py
+++ b/eitprocessing/datahandling/continuousdata.py
@@ -221,8 +221,8 @@ def _sliced_copy(
     ) -> Self:
         # TODO: check correct implementation
         cls = self.__class__
-        time = self.time[start_index:end_index]
-        values = self.values[start_index:end_index]
+        time = np.copy(self.time[start_index:end_index])
+        values = np.copy(self.values[start_index:end_index])
         description = f"Slice ({start_index}-{end_index}) of <{self.description}>"
 
         return cls(
diff --git a/eitprocessing/datahandling/eitdata.py b/eitprocessing/datahandling/eitdata.py
index 65009debe..2dde595d8 100644
--- a/eitprocessing/datahandling/eitdata.py
+++ b/eitprocessing/datahandling/eitdata.py
@@ -99,10 +99,10 @@ def _sliced_copy(
         newlabel: str,  # noqa: ARG002
     ) -> Self:
         cls = self.__class__
-        time = self.time[start_index:end_index]
+        time = np.copy(self.time[start_index:end_index])
         nframes = len(time)
 
-        pixel_impedance = self.pixel_impedance[start_index:end_index, :, :]
+        pixel_impedance = np.copy(self.pixel_impedance[start_index:end_index, :, :])
 
         return cls(
             path=self.path,
diff --git a/pyproject.toml b/pyproject.toml
index 45a46a665..bc908fdd9 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -4,7 +4,7 @@ build-backend = "setuptools.build_meta"
 
 [project]
 name = "eitprocessing"
-version = "1.1.0"
+version = "1.1.1"
 description = "Processing of lung image data from electrical impedance tomography."
 readme = "README.md"
 requires-python = ">=3.10"
@@ -156,7 +156,7 @@ isort.known-first-party = ["eitprocessing"]
 "docs/*" = ["ALL"]
 
 [tool.bumpversion]
-current_version = "1.1.0"
+current_version = "1.1.1"
 
 [[tool.bumpversion.files]]
 filename = "pyproject.toml"