diff --git a/Apps/LekaActivityUIExplorer/Resources/GEKNewSystem/activities/activity-xylophone-octatonic.yml b/Apps/LekaActivityUIExplorer/Resources/GEKNewSystem/activities/activity-xylophone-octatonic.yml
deleted file mode 100644
index 52885715d6..0000000000
--- a/Apps/LekaActivityUIExplorer/Resources/GEKNewSystem/activities/activity-xylophone-octatonic.yml
+++ /dev/null
@@ -1,15 +0,0 @@
-# Leka - iOS Monorepo
-# Copyright 2023 APF France handicap
-# SPDX-License-Identifier: Apache-2.0
-
-id: 7fe97b08432f4ec0a1556f6f8734a99e
-name: Xylophone Octatonic
-description: L'objectif est de jouer de la musique à l'aide du xylophone
-image: activity_color_recognition_1
-sequence:
-  - exercises:
-      - instructions: Joue du xylophone avec Leka
-        interface: musicalInstruments
-        payload:
-          instrument: xylophone
-          scale: majorOctatonic
diff --git a/Apps/LekaActivityUIExplorer/Sources/GEKNewSystem/GEKNewSystemView.swift b/Apps/LekaActivityUIExplorer/Sources/GEKNewSystem/GEKNewSystemView.swift
index 2d57148ba0..0f5972b022 100644
--- a/Apps/LekaActivityUIExplorer/Sources/GEKNewSystem/GEKNewSystemView.swift
+++ b/Apps/LekaActivityUIExplorer/Sources/GEKNewSystem/GEKNewSystemView.swift
@@ -38,7 +38,6 @@ let kActivities: [Activity] = [
     ContentKit.decodeActivity("activity-hideAndSeek"),
     ContentKit.decodeActivity("activity-xylophone-pentatonic"),
     ContentKit.decodeActivity("activity-xylophone-heptatonic"),
-    ContentKit.decodeActivity("activity-xylophone-octatonic"),
 ]
 
 struct GEKNewSystemView: View {
diff --git a/Modules/GameEngineKit/Sources/_NewSystem/Utils/MIDIScale.swift b/Modules/GameEngineKit/Sources/_NewSystem/Utils/MIDIScale.swift
index 4e59673a46..fa5455d230 100644
--- a/Modules/GameEngineKit/Sources/_NewSystem/Utils/MIDIScale.swift
+++ b/Modules/GameEngineKit/Sources/_NewSystem/Utils/MIDIScale.swift
@@ -7,15 +7,12 @@ import AudioKit
 enum MIDIScale: String {
     case majorPentatonic
     case majorHeptatonic
-    case majorOctatonic
 
     var notes: [MIDINoteNumber] {
         switch self {
             case .majorPentatonic:
                 return [24, 26, 28, 31, 33]
             case .majorHeptatonic:
-                return [24, 26, 28, 29, 31, 33, 35]
-            case .majorOctatonic:
                 return [24, 26, 28, 29, 31, 33, 35, 36]
         }
     }