diff --git a/CHANGELOG.md b/CHANGELOG.md
index c8538f088..f528cdff5 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -16,6 +16,9 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 
 ## Changes March 2020
 
+### Fixed
+- GAP: fixed gap_set_scan_parameters() if issued right before gap_start_scan() 
+
 ### Added
 GATT Client: allow to register for any notification/indication and/or any connection
 hci_cmd: added hci_read_inquiry_scan_activity and hci_write_inquiry_scan_activity
diff --git a/src/hci.c b/src/hci.c
index eeba80161..5cbde15ad 100644
--- a/src/hci.c
+++ b/src/hci.c
@@ -3413,17 +3413,22 @@ static void hci_run(void){
     && ((hci_stack->le_own_addr_type == BD_ADDR_TYPE_LE_PUBLIC) || hci_stack->le_random_address_set)){
 
 #ifdef ENABLE_LE_CENTRAL
-        // handle le scan
-        if ((hci_stack->le_scanning_enabled != hci_stack->le_scanning_active)){
-            hci_stack->le_scanning_active = hci_stack->le_scanning_enabled;
-            hci_send_cmd(&hci_le_set_scan_enable, hci_stack->le_scanning_enabled, 0);
+        // parameter change requires scanning to be stopped first
+        if (hci_stack->le_scan_type != 0xff) {
+            if (hci_stack->le_scanning_active){
+                hci_stack->le_scanning_active = 0;
+                hci_send_cmd(&hci_le_set_scan_enable, 0, 0);
+            } else {
+                int scan_type = (int) hci_stack->le_scan_type;
+                hci_stack->le_scan_type = 0xff;
+                hci_send_cmd(&hci_le_set_scan_parameters, scan_type, hci_stack->le_scan_interval, hci_stack->le_scan_window, hci_stack->le_own_addr_type, 0);
+            }
             return;
         }
-        if (hci_stack->le_scan_type != 0xff){
-            // defaults: active scanning, accept all advertisement packets
-            int scan_type = hci_stack->le_scan_type;
-            hci_stack->le_scan_type = 0xff;
-            hci_send_cmd(&hci_le_set_scan_parameters, scan_type, hci_stack->le_scan_interval, hci_stack->le_scan_window, hci_stack->le_own_addr_type, 0);
+        // finally, we can enable/disable le scan
+        if ((hci_stack->le_scanning_enabled && !hci_stack->le_scanning_active)){
+            hci_stack->le_scanning_active = hci_stack->le_scanning_enabled;
+            hci_send_cmd(&hci_le_set_scan_enable, hci_stack->le_scanning_enabled, 0);
             return;
         }
 #endif