diff --git a/Hardware/README.md b/Hardware/README.md
index 1846611f..b83cd765 100644
--- a/Hardware/README.md
+++ b/Hardware/README.md
@@ -1 +1,3 @@
 Most of these are prototypes and have defects. Use them as references for concepts only.
+
+Known defect in Interface.brd is the differential signals are not routed correctly.