diff --git a/mne/_freesurfer.py b/mne/_freesurfer.py
index 67a27d59860..7fd4559cf00 100644
--- a/mne/_freesurfer.py
+++ b/mne/_freesurfer.py
@@ -141,7 +141,7 @@ def _get_mri_info_data(mri, data):
     if data:
         assert mgz is not None
         out["mri_vox_t"] = invert_transform(out["vox_mri_t"])
-        out["data"] = np.asarray(mgz.dataobj)
+        out["data"] = np.array(mgz.dataobj)
     return out
 
 
diff --git a/mne/source_space/_source_space.py b/mne/source_space/_source_space.py
index 11834cc7631..eaaf77bf2ca 100644
--- a/mne/source_space/_source_space.py
+++ b/mne/source_space/_source_space.py
@@ -1377,7 +1377,7 @@ def _write_one_source_space(fid, this, verbose=None):
         mri_width, mri_height, mri_depth, nvox = _src_vol_dims(this)
         interpolator = this.get("interpolator")
         if interpolator is None:
-            interpolator = csr_matrix((nvox, this["np"]))
+            interpolator = csr_matrix((nvox, this["np"]), copy=True)
         write_float_sparse_rcs(
             fid, FIFF.FIFF_MNE_SOURCE_SPACE_INTERPOLATOR, interpolator
         )
@@ -2390,7 +2390,9 @@ def _add_interpolator(sp):
             indices = interp.indices[mask]
             data = interp.data[mask]
             assert data.shape == indices.shape == (indptr[-1],)
-            this_interp = csr_matrix((data, indices, indptr), shape=interp.shape)
+            this_interp = csr_matrix(
+                (data, indices, indptr), shape=interp.shape, copy=True
+            )
         s["interpolator"] = this_interp
         logger.info(
             "    %d/%d nonzero values for %s"
@@ -2415,7 +2417,7 @@ def _grid_interp(from_shape, to_shape, trans, order=1, inuse=None):
     data = np.concatenate(data)
     indices = np.concatenate(indices)
     indptr = np.cumsum(indptr)
-    interp = csr_matrix((data, indices, indptr), shape=shape)
+    interp = csr_matrix((data, indices, indptr), shape=shape, copy=True)
     return interp