diff --git a/pystencils/gpu/gpu_array_handler.py b/pystencils/gpu/gpu_array_handler.py
index f25ba5ffc2de19378bbcecd3ac7d4cbee9f4cf83..9031036f42a29f5a8adb2e08905c990ec8b441e8 100644
--- a/pystencils/gpu/gpu_array_handler.py
+++ b/pystencils/gpu/gpu_array_handler.py
@@ -28,7 +28,7 @@ class GPUArrayHandler:
     @staticmethod
     def to_gpu(numpy_array):
         swaps = _get_index_swaps(numpy_array)
-        if numpy_array.base is not None:
+        if numpy_array.base is not None and isinstance(numpy_array.base, np.ndarray):
             with cp.cuda.Device(pystencils.GPU_DEVICE):
                 gpu_array = cp.asarray(numpy_array.base)
             for a, b in reversed(swaps):
@@ -39,7 +39,7 @@ class GPUArrayHandler:
 
     @staticmethod
     def upload(array, numpy_array):
-        if numpy_array.base is not None:
+        if numpy_array.base is not None and isinstance(numpy_array.base, np.ndarray):
             with cp.cuda.Device(pystencils.GPU_DEVICE):
                 array.base.set(numpy_array.base)
         else:
@@ -48,7 +48,7 @@ class GPUArrayHandler:
 
     @staticmethod
     def download(array, numpy_array):
-        if numpy_array.base is not None:
+        if numpy_array.base is not None and isinstance(numpy_array.base, np.ndarray):
             with cp.cuda.Device(pystencils.GPU_DEVICE):
                 numpy_array.base[:] = array.base.get()
         else:
@@ -92,7 +92,7 @@ class GPUNotAvailableHandler:
 
 def _get_index_swaps(array):
     swaps = []
-    if array.base is not None:
+    if array.base is not None and isinstance(array.base, np.ndarray):
         for stride in array.base.strides:
             index_base = array.base.strides.index(stride)
             index_view = array.strides.index(stride)