docs: Update README with workaround for keypress issue

README.md

@@ -117,7 +117,7 @@ Now you can run the binary from `./target/debug/cherryrgb_cli`
 If the interaction with the keyboard is fine as root-user, you need to configure udev
 to adjust the ownership of the device handle, so a regular user can access it.
 
-The repository contains an example udev rule file `udev/99-cherryrgb.rules`.
+The repository contains an example udev rule file [`udev/99-cherryrgb.rules`](https://github.com/skraus-dev/cherryrgb-rs/blob/master/udev/99-cherryrgb.rules).
 
 You might want to adjust it to only handle your specific product id (check via `lsusb`).
 
@@ -129,6 +129,15 @@ In the following example we assume your product id is **0x00dd**.
 
 3. Finally, reload the udev rules via `udevadm control --reload` and apply them using `udevadm trigger` or by re-plugging your keyboard.
 
+### Keyboard events are processed very slow after setting LEDs
+
+This is a known issue in the keyboard firmware.
+It is mentioned here: <https://bbs.archlinux.org/viewtopic.php?id=267365>
+
+- **Proper** way to fix it: **Contact Cherry Support**
+
+- **Workaround**: Comment out the respective line in [`99-cherryrgb.rules`](https://github.com/skraus-dev/cherryrgb-rs/blob/master/udev/99-cherryrgb.rules) and reload/trigger the udev rule.
+
 ## Disclaimer
 
 Use at your own risk.

udev/99-cherryrgb.rules

@@ -1 +1,13 @@
-SUBSYSTEMS=="usb", ATTR{idVendor}=="046a", ATTR{idProduct}=="*", MODE="0666"
+######################################
+# udev rule for Cherry RGB keyboards #
+######################################
+
+SUBSYSTEMS=="usb", ATTR{idVendor}=="046a", ATTR{idProduct}=="*", MODE="0666"
+
+# There is a known bug in the keyboard firmware that produces loads of keyevents
+# and makes the input go very sluggish / prevent logins over TTY
+#
+# Reference: https://bbs.archlinux.org/viewtopic.php?id=267365
+#
+# Uncomment the following line to workaround this issue
+# ACTION=="add", SUBSYSTEM=="input", ATTRS{idVendor}=="046a", ATTRS{idProduct}=="*", ATTR{capabilities/ev}=="10001f", ATTR{inhibited}="1"