diff --git a/README.md b/README.md
index 3c91761..32a3ec7 100644
--- a/README.md
+++ b/README.md
@@ -35,6 +35,9 @@ Each PCB connects to 10 LEDs, and the PCB can be chained together to
 form a single WS2812 chain.  There are 83 LEDs in the current version, so a total of 9 of these PCBs is required.
 The ESP32-C3 needs to be soldered to the first PCB.
 
+> :warning: **There is a small issue with V1.0 of the PCB!** (Please check the version number on the silk screen!):
+> Pins 1 and 4 of the OUT pin header are swapped - this can be easily worked around by swapping wires number 1 and 4 in the JST connector plugged into this header.
+
 ### esp32/
 
 The PlatformIO Arduino project for the ESP32.  It perfoms the following tasks: