diff --git a/HELP.md b/HELP.md
index 5e3913d8..b66b4902 100644
--- a/HELP.md
+++ b/HELP.md
@@ -83,11 +83,20 @@ keycode, use a custom mapping that starts at 255 and just offsets xmodmap
 by 255. The correct capabilities need to exist this time. Everything below
 255 is disabled. This mapping is applied to key-mappers custom /dev node.
 
-Each preset uses the same key-mapper-offset-symbol file and the same
-empty-symbol file to disable the keys of the original device. This avoids
-having to manage user defined presets in /usr. But it could be extended to
-support custom xkb symbol files in the future, to e.g. map `10` to 'b', and
-`shift+10` to 'c'.
+However, if you try to map Shift to button 10 of your mouse, and use
+mouse-shift + keyboard-1, you need to press keyboard-1 again to do anything.
+I assume this is because:
+- mouse-10 down
+- keymapper says: shift down
+- keyboard-10 down (down again? X/Linux ignores that)
+- keyboard-10 up
+- keyboard-10 down, "!" written
+
+**Seventh, final solution** By grabbing the mouse device (EVIOCGRAB) this
+won't happen. Since this prevents all the keycodes from doing stuff, no
+empty xkb symbols file is needed anymore. I can basically do the fifth idea
+from above.
+
 
 # How I would have liked it to be
 
diff --git a/keymapper/getdevices.py b/keymapper/getdevices.py
index 028688cd..7b6dc1fa 100644
--- a/keymapper/getdevices.py
+++ b/keymapper/getdevices.py
@@ -62,7 +62,12 @@ class _GetDevicesProcess(multiprocessing.Process):
         for device in devices:
             # only keyboard devices
             # https://www.kernel.org/doc/html/latest/input/event-codes.html
-            if evdev.ecodes.EV_KEY not in device.capabilities().keys():
+            capabilities = device.capabilities().keys()
+            if evdev.ecodes.EV_KEY not in capabilities:
+                continue
+
+            if evdev.ecodes.EV_REL in capabilities:
+                # skip devices that control movement
                 continue
 
             usb = device.phys.split('/')[0]
diff --git a/keymapper/injector.py b/keymapper/injector.py
index 58b61c0c..2187f882 100644
--- a/keymapper/injector.py
+++ b/keymapper/injector.py
@@ -109,6 +109,13 @@ class KeycodeInjector:
         loop = asyncio.new_event_loop()
         asyncio.set_event_loop(loop)
         device = evdev.InputDevice(path)
+        """try:
+            # grab to avoid e.g. the disabled keycode of 10 to confuse X,
+            # especially when one of the buttons of your mouse also uses 10
+            device.grab()
+        except IOError:
+            logger.error('Cannot grab %s', path)"""
+
         # foo = evdev.InputDevice('/dev/input/event2')
         keymapper_device = evdev.UInput(
             name=DEV_NAME,
@@ -127,7 +134,7 @@ class KeycodeInjector:
             if event.type != evdev.ecodes.EV_KEY:
                 continue
 
-            if event.code == 2:
+            if event.value == 2:
                 # linux does them itself, no need to trigger them
                 continue
 
@@ -141,7 +148,7 @@ class KeycodeInjector:
                 # unknown keycode, forward it
                 continue
             else:
-                target_keycode = internal_mapping.get_keycode(character)
+                target_keycode = system_mapping.get_keycode(character)
                 if target_keycode is None:
                     logger.error(
                         'Cannot find character %s in the internal mapping',
@@ -158,8 +165,8 @@ class KeycodeInjector:
                 # fine. I came up with that after randomly poking around in,
                 # frustration. I don't know of any helpful resource that
                 # explains this
-                # TODO still needed? if no, add to HELP.md
-            time.sleep(0.015)
+                # TODO still needed? if yes, add to HELP.md
+                time.sleep(0.005)
 
             logger.debug2(
                 'got code:%s value:%s, maps to code:%s char:%s',