diff --git a/bootstrapvz/base/fs/volume.py b/bootstrapvz/base/fs/volume.py
index 0a17f61..043094a 100644
--- a/bootstrapvz/base/fs/volume.py
+++ b/bootstrapvz/base/fs/volume.py
@@ -70,6 +70,7 @@ class Volume(FSMProxy):
 		rather than a loopback device or a network block device.
 
 		:param _e_obj e: Event object containing arguments to create()
+
 		Keyword arguments to link_dm_node() are:
 
 		:param int logical_start_sector: The sector the volume should start at in the new volume
diff --git a/docs/base/pkg.rst b/docs/base/pkg.rst
index 1a8db8b..4625358 100644
--- a/docs/base/pkg.rst
+++ b/docs/base/pkg.rst
@@ -16,7 +16,7 @@ Sources list
     :private-members:
 
 Preferences list
-------------
+----------------
 .. automodule:: bootstrapvz.base.pkg.preferenceslist
     :members:
     :private-members:
diff --git a/tox.ini b/tox.ini
index 17db141..e229a8d 100644
--- a/tox.ini
+++ b/tox.ini
@@ -20,7 +20,7 @@ deps =
     sphinx
 commands =
     ./taskoverview.py --output docs/_static/graph.json
-    sphinx-build -b html -d docs/_build/html/doctrees docs docs/_build/html
+    sphinx-build -W -b html -d docs/_build/html/doctrees docs docs/_build/html
 
 [testenv:docs-serve]
 changedir = docs/_build/html