diff --git a/config.c b/config.c
index 57c239b..98e8f1c 100644
--- a/config.c
+++ b/config.c
@@ -254,7 +254,7 @@ struct config_item config_tab[] = {
 	GLOB_ITEM_DBL("step_threshold", 0.0, 0.0, DBL_MAX),
 	GLOB_ITEM_INT("summary_interval", 0, INT_MIN, INT_MAX),
 	PORT_ITEM_INT("syncReceiptTimeout", 0, 0, UINT8_MAX),
-	GLOB_ITEM_INT("tc_spanning_tree", 0, 1, 1),
+	GLOB_ITEM_INT("tc_spanning_tree", 0, 0, 1),
 	GLOB_ITEM_INT("timeSource", INTERNAL_OSCILLATOR, 0x10, 0xfe),
 	GLOB_ITEM_ENU("time_stamping", TS_HARDWARE, timestamping_enu),
 	PORT_ITEM_INT("transportSpecific", 0, 0, 0x0F),