diff --git a/kernel/iec_timing.h b/kernel/iec_timing.h
index 10632ab..77670a8 100644
--- a/kernel/iec_timing.h
+++ b/kernel/iec_timing.h
@@ -30,7 +30,7 @@
  * confirmed-working reference listener (5 us). sd2iec / the 1571 ROM
  * use a comparable few-microsecond debounce. Far shorter than a real IEC bit
  * (tens of us), so it never smears valid data. */
-#define IEC_DEBOUNCE_US      5
+#define IEC_DEBOUNCE_US      10
 
 /* Between-bytes minimum hold before the talker releases CLK for the next byte
  * (Tbb). We simply wait for the next CLK transition; this is documentary. */