add input consistency images & rumble strength info

src/configuration.md

@@ -257,6 +257,18 @@ Press `R+Start` while in config mode to display the axis smoothing values on eac
 
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+## Rumble Strength Adjustment
+
+**Button Combo:** `A+B+Du/Dd`
+
+- Press `A+B` and `D-pad up/down` to increase/decrease the rumble strength.
+- The scale goes from `0` to `11`.
+  - `9` is roughly equivalent to an OEM controller's rumble.
+  - `0` turns off rumble entirely.
+- When adjusting, the current rumble strength will be displayed on the analog stick's Y axis.
+
+---
+
 ## Input Consistency Mode Toggle
 
 **Button Combo:** `A+Z+Start`
@@ -269,7 +281,11 @@ Cycles the input consistency setting through its three modes and displays which
 
 For more information about the different input consistency modes, consult the [Input Consistency Mode](./input-consistency.md#input-consistency-modes) list.
 
-> **NOTE:** This setting will only become active upon unplugging and replugging the controller.
+> **NOTE:** This setting will only become active upon unplugging and replugging the controller. The controller will then indicate the mode it's in by changing its device name. You can then use your operating system's device viewer to have a look at the device name and determine which mode is currently active. For example, under Linux you can run `lsusb -v` and look for `NaxGCC`:
+>
+> <img src="./assets/consistency-mode.png" style="display: block; margin-left: auto; margin-right: auto;" />
+>
+> <img src="./assets/consistency-mode-2.png" style="display: block; margin-left: auto; margin-right: auto;" />
 
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