diff --git a/geoapps/inversion/components/models.py b/geoapps/inversion/components/models.py
index 35009ae80..64a2c6b38 100644
--- a/geoapps/inversion/components/models.py
+++ b/geoapps/inversion/components/models.py
@@ -118,6 +118,7 @@ def starting(self):
         mstart = self._starting.model
 
         if mstart is not None and self.is_sigma:
+            mstart = mstart.copy()
             mstart = np.log(mstart)
 
         return mstart
@@ -132,11 +133,13 @@ def reference(self):
         if mref is None:
             mref = self.starting
             self.driver.params.alpha_s = 0.0
-        elif self.is_sigma & (all(mref == 0)):
-            mref = self.starting
-            self.driver.params.alpha_s = 0.0
         else:
-            mref = np.log(mref) if self.is_sigma else mref
+            mref = mref.copy()
+            if self.is_sigma & (all(mref == 0)):
+                mref = self.starting
+                self.driver.params.alpha_s = 0.0
+            else:
+                mref = np.log(mref) if self.is_sigma else mref
         return mref
 
     @property
@@ -146,6 +149,8 @@ def lower_bound(self):
         if lbound is None:
             return -np.inf
 
+        lbound = lbound.copy()
+
         if self.is_sigma:
             is_finite = np.isfinite(lbound)
             lbound[is_finite] = np.log(lbound[is_finite])
@@ -158,6 +163,7 @@ def upper_bound(self):
         if ubound is None:
             return np.inf
 
+        ubound = ubound.copy()
         if self.is_sigma:
             is_finite = np.isfinite(ubound)
             ubound[is_finite] = np.log(ubound[is_finite])
@@ -169,6 +175,7 @@ def conductivity(self):
         mstart = self._conductivity.model
 
         if mstart is not None and self.is_sigma:
+            mstart = mstart.copy()
             mstart = np.log(mstart)
 
         return mstart
diff --git a/geoapps/inversion/joint/driver.py b/geoapps/inversion/joint/driver.py
index a7bbdafe6..374557b9b 100644
--- a/geoapps/inversion/joint/driver.py
+++ b/geoapps/inversion/joint/driver.py
@@ -69,6 +69,7 @@ def drivers(self) -> list[InversionDriver] | None:
                 group = self.workspace.get_entity(group.uid)[0]
                 ui_json = group.options
                 ui_json["geoh5"] = self.workspace
+                ui_json["workspace_geoh5"] = None
 
                 ifile = InputFile(ui_json=ui_json)
                 mod_name, class_name = DRIVER_MAP.get(ifile.data["inversion_type"])