src/audio_core/common/feature_support.h

@@ -1,3 +1,6 @@
+// SPDX-FileCopyrightText: Copyright 2025 Eden Emulator Project
+// SPDX-License-Identifier: GPL-3.0-or-later
+
 // SPDX-FileCopyrightText: Copyright 2022 yuzu Emulator Project
 // SPDX-License-Identifier: GPL-2.0-or-later
 
@@ -44,6 +47,8 @@ enum class SupportTags {
     DelayChannelMappingChange,
     ReverbChannelMappingChange,
     I3dl2ReverbChannelMappingChange,
+    DecodingBehaviourFlag,
+    BiquadFilterParameterForSplitter,
 
     // Not a real tag, just here to get the count.
     Size
@@ -87,6 +92,8 @@ constexpr bool CheckFeatureSupported(SupportTags tag, u32 user_revision) {
             {SupportTags::DelayChannelMappingChange, 11},
             {SupportTags::ReverbChannelMappingChange, 11},
             {SupportTags::I3dl2ReverbChannelMappingChange, 11},
+            {SupportTags::DecodingBehaviourFlag, 12},
+            {SupportTags::BiquadFilterParameterForSplitter, 13},
         }};
 
     const auto& feature =

src/audio_core/renderer/audio_renderer.h

@@ -1,3 +1,6 @@
+// SPDX-FileCopyrightText: Copyright 2025 Eden Emulator Project
+// SPDX-License-Identifier: GPL-3.0-or-later
+
 // SPDX-FileCopyrightText: Copyright 2022 yuzu Emulator Project
 // SPDX-License-Identifier: GPL-2.0-or-later
 
@@ -93,6 +96,7 @@ private:
     bool system_registered{};
     /// Audio render system, main driver of audio rendering
     System system;
+    bool m_volume_ramp_reset = false;
 };
 
 } // namespace Renderer

src/audio_core/renderer/splitter/parameters.h

@@ -0,0 +1,22 @@
+// SPDX-FileCopyrightText: Copyright 2025 Eden Emulator Project
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#pragma once
+
+#include "common/common_types.h"
+
+namespace AudioCore::Renderer {
+
+/**
+ * Input struct passed to a splitter destination in REV13.
+ */
+struct SplitterDestinationInParameter {
+    /* 0x00 */ s32 magic;
+    /* 0x04 */ s32 id;
+    /* 0x08 */ bool reset_prev_volume;
+    /* 0x09 */ u8 reserved[11];  // Padding to align to 0x14
+};
+static_assert(sizeof(SplitterDestinationInParameter) == 0x14,
+              "SplitterDestinationInParameter must be 0x14 bytes.");
+
+} // namespace AudioCore::Renderer

src/audio_core/renderer/splitter/splitter_context.cpp

@@ -1,9 +1,13 @@
+// SPDX-FileCopyrightText: Copyright 2025 Eden Emulator Project
+// SPDX-License-Identifier: GPL-3.0-or-later
+
 // SPDX-FileCopyrightText: Copyright 2022 yuzu Emulator Project
 // SPDX-License-Identifier: GPL-2.0-or-later
 
 #include "audio_core/common/audio_renderer_parameter.h"
 #include "audio_core/common/workbuffer_allocator.h"
 #include "audio_core/renderer/behavior/behavior_info.h"
+#include "audio_core/renderer/splitter/parameters.h"
 #include "audio_core/renderer/splitter/splitter_context.h"
 #include "common/alignment.h"
 
@@ -134,19 +138,30 @@ u32 SplitterContext::UpdateInfo(const u8* input, u32 offset, const u32 splitter_
 
 u32 SplitterContext::UpdateData(const u8* input, u32 offset, const u32 count) {
     for (u32 i = 0; i < count; i++) {
-        auto data_header{
+        const auto* data_header =
-            reinterpret_cast<const SplitterDestinationData::InParameter*>(input + offset)};
+            reinterpret_cast<const SplitterDestinationData::InParameter*>(input + offset);
 
         if (data_header->magic != GetSplitterSendDataMagic()) {
             continue;
         }
 
-        if (data_header->id < 0 || data_header->id > destinations_count) {
+        if (data_header->id < 0 || data_header->id >= destinations_count) {
             continue;
         }
 
-        splitter_destinations[data_header->id].Update(*data_header);
+        auto& destination = splitter_destinations[data_header->id];
-        offset += sizeof(SplitterDestinationData::InParameter);
+        destination.Update(*data_header);
+
+        // REV13: Set reset flag if present in extended struct
+        const auto* reset_data =
+            reinterpret_cast<const SplitterDestinationInParameter*>(
+                input + offset + sizeof(SplitterDestinationData::InParameter));
+        if (reset_data->reset_prev_volume) {
+            destination.SetResetPrevVolume();
+        }
+
+        offset += sizeof(SplitterDestinationData::InParameter) +
+                  sizeof(SplitterDestinationInParameter);
     }
 
     return offset;
@@ -214,4 +229,9 @@ u64 SplitterContext::CalcWorkBufferSize(const BehaviorInfo& behavior,
     return size;
 }
 
+std::span<SplitterDestinationData> SplitterContext::GetDestinations() {
+    return std::span<SplitterDestinationData>{splitter_destinations,
+                                              static_cast<size_t>(destinations_count)};
+}
+
 } // namespace AudioCore::Renderer

src/audio_core/renderer/splitter/splitter_context.h

@@ -1,3 +1,6 @@
+// SPDX-FileCopyrightText: Copyright 2025 Eden Emulator Project
+// SPDX-License-Identifier: GPL-3.0-or-later
+
 // SPDX-FileCopyrightText: Copyright 2022 yuzu Emulator Project
 // SPDX-License-Identifier: GPL-2.0-or-later
 
@@ -159,6 +162,13 @@ public:
     static u64 CalcWorkBufferSize(const BehaviorInfo& behavior,
                                   const AudioRendererParameterInternal& params);
 
+    /**
+     * Get all active splitter destinations.
+     *
+     * @return Span of splitter destinations.
+     */
+    std::span<SplitterDestinationData> GetDestinations();
+
 private:
     /**
      * Setup the context.

src/audio_core/renderer/splitter/splitter_destinations_data.cpp

@@ -1,3 +1,6 @@
+// SPDX-FileCopyrightText: Copyright 2025 Eden Emulator Project
+// SPDX-License-Identifier: GPL-3.0-or-later
+
 // SPDX-FileCopyrightText: Copyright 2022 yuzu Emulator Project
 // SPDX-License-Identifier: GPL-2.0-or-later
 
@@ -84,4 +87,16 @@ void SplitterDestinationData::SetNext(SplitterDestinationData* next_) {
     next = next_;
 }
 
+void SplitterDestinationData::SetResetPrevVolume() {
+    m_reset_prev_volume = true;
+}
+
+bool SplitterDestinationData::ShouldResetPrevVolume() const {
+    return m_reset_prev_volume;
+}
+
+void SplitterDestinationData::ClearResetPrevVolume() {
+    m_reset_prev_volume = false;
+}
+
 } // namespace AudioCore::Renderer

src/audio_core/renderer/splitter/splitter_destinations_data.h

@@ -1,3 +1,6 @@
+// SPDX-FileCopyrightText: Copyright 2025 Eden Emulator Project
+// SPDX-License-Identifier: GPL-3.0-or-later
+
 // SPDX-FileCopyrightText: Copyright 2022 yuzu Emulator Project
 // SPDX-License-Identifier: GPL-2.0-or-later
 
@@ -115,6 +118,21 @@ public:
      */
     void SetNext(SplitterDestinationData* next);
 
+    /**
+    * REV13: Called during UpdateData() if the struct's flag is set
+    */
+    void SetResetPrevVolume();
+
+    /**
+    * REV13: Called during GenerateCommand() to check for a reset
+    */
+    bool ShouldResetPrevVolume() const;
+
+    /**
+    * REV13: Called after reset is applied to clear the flag
+    */
+    void ClearResetPrevVolume();
+
 private:
     /// Id of this destination
     const s32 id;
@@ -130,6 +148,8 @@ private:
     bool in_use{};
     /// Does this destination need its volumes updated?
     bool need_update{};
+    /// REV13: Flag to reset previous volume ramps
+    bool m_reset_prev_volume{false};
 };
 
 } // namespace AudioCore::Renderer

src/audio_core/renderer/system.cpp

@@ -1,3 +1,6 @@
+// SPDX-FileCopyrightText: Copyright 2025 Eden Emulator Project
+// SPDX-License-Identifier: GPL-3.0-or-later
+
 // SPDX-FileCopyrightText: Copyright 2022 yuzu Emulator Project
 // SPDX-License-Identifier: GPL-2.0-or-later
 
@@ -688,6 +691,7 @@ u64 System::GenerateCommand(std::span<u8> in_command_buffer,
                                        sink_context,   splitter_context,     perf_manager};
 
     voice_context.SortInfo();
+
     command_generator.GenerateVoiceCommands();
 
     const auto start_estimated_time{drop_voice_param *
@@ -697,6 +701,17 @@ u64 System::GenerateCommand(std::span<u8> in_command_buffer,
     command_generator.GenerateFinalMixCommands();
     command_generator.GenerateSinkCommands();
 
+    // REV13: Reset previous volumes for any splitter destinations requesting it
+    for (auto& destination : splitter_context.GetDestinations()) {
+        if (destination.ShouldResetPrevVolume()) {
+            for (auto& volume : destination.GetMixVolumePrev()) {
+                volume = 0.0f;
+            }
+            destination.ClearResetPrevVolume();
+        }
+    }
+
+
     if (drop_voice) {
         f32 time_limit_percent{70.0f};
         if (render_context.behavior->IsAudioRendererProcessingTimeLimit80PercentSupported()) {

src/core/hle/service/audio/audio_device.cpp

@@ -1,3 +1,6 @@
+// SPDX-FileCopyrightText: Copyright 2025 Eden Emulator Project
+// SPDX-License-Identifier: GPL-3.0-or-later
+
 // SPDX-FileCopyrightText: Copyright 2024 yuzu Emulator Project
 // SPDX-License-Identifier: GPL-2.0-or-later
 
@@ -29,12 +32,12 @@ IAudioDevice::IAudioDevice(Core::System& system_, u64 applet_resource_user_id, u
         {12, D<&IAudioDevice::QueryAudioDeviceOutputEvent>, "QueryAudioDeviceOutputEvent"},
         {13, D<&IAudioDevice::GetActiveAudioDeviceName>, "GetActiveAudioOutputDeviceName"},
         {14, D<&IAudioDevice::ListAudioOutputDeviceName>, "ListAudioOutputDeviceName"},
-        {15, nullptr, "AcquireAudioInputDeviceNotification"},       // 17.0.0+
+        {15, D<&IAudioDevice::AcquireAudioInputDeviceNotification>, "AcquireAudioInputDeviceNotification"},       // 17.0.0+
-        {16, nullptr, "ReleaseAudioInputDeviceNotification"},       // 17.0.0+
+        {16, D<&IAudioDevice::ReleaseAudioInputDeviceNotification>, "ReleaseAudioInputDeviceNotification"},       // 17.0.0+
-        {17, nullptr, "AcquireAudioOutputDeviceNotification"},      // 17.0.0+
+        {17, D<&IAudioDevice::AcquireAudioOutputDeviceNotification>, "AcquireAudioOutputDeviceNotification"},     // 17.0.0+
-        {18, nullptr, "ReleaseAudioOutputDeviceNotification"},      // 17.0.0+
+        {18, D<&IAudioDevice::ReleaseAudioOutputDeviceNotification>, "ReleaseAudioOutputDeviceNotification"},     // 17.0.0+
-        {19, nullptr, "SetAudioDeviceOutputVolumeAutoTuneEnabled"}, // 18.0.0+
+        {19, D<&IAudioDevice::SetAudioDeviceOutputVolumeAutoTuneEnabled>, "SetAudioDeviceOutputVolumeAutoTuneEnabled"}, // 18.0.0+
-        {20, nullptr, "IsAudioDeviceOutputVolumeAutoTuneEnabled"}   // 18.0.0+
+        {20, D<&IAudioDevice::IsAudioDeviceOutputVolumeAutoTuneEnabled>, "IsAudioDeviceOutputVolumeAutoTuneEnabled"}    // 18.0.0+
     };
     RegisterHandlers(functions);
 
@@ -166,4 +169,37 @@ Result IAudioDevice::ListAudioOutputDeviceName(
     R_SUCCEED();
 }
 
+Result IAudioDevice::AcquireAudioInputDeviceNotification(OutCopyHandle<Kernel::KEvent> out_event_handle, u64 device_id) {
+    LOG_DEBUG(Service_Audio, "(STUBBED) AcquireAudioInputDeviceNotification called. device_id={:016X}", device_id);
+    *out_event_handle = event; // Reuse existing stub logic as placeholder
+    R_SUCCEED();
+}
+
+Result IAudioDevice::ReleaseAudioInputDeviceNotification(u64 device_id) {
+    LOG_DEBUG(Service_Audio, "(STUBBED) ReleaseAudioInputDeviceNotification called. device_id={:016X}", device_id);
+    R_SUCCEED();
+}
+
+Result IAudioDevice::AcquireAudioOutputDeviceNotification(OutCopyHandle<Kernel::KEvent> out_event_handle, u64 device_id) {
+    LOG_DEBUG(Service_Audio, "(STUBBED) AcquireAudioOutputDeviceNotification called. device_id={:016X}", device_id);
+    *out_event_handle = event; // Reuse existing stub logic as placeholder
+    R_SUCCEED();
+}
+
+Result IAudioDevice::ReleaseAudioOutputDeviceNotification(u64 device_id) {
+    LOG_DEBUG(Service_Audio, "(STUBBED) ReleaseAudioOutputDeviceNotification called. device_id={:016X}", device_id);
+    R_SUCCEED();
+}
+
+Result IAudioDevice::SetAudioDeviceOutputVolumeAutoTuneEnabled(bool enabled) {
+    LOG_DEBUG(Service_Audio, "(STUBBED) SetAudioDeviceOutputVolumeAutoTuneEnabled called. enabled={}", enabled);
+    R_SUCCEED();
+}
+
+Result IAudioDevice::IsAudioDeviceOutputVolumeAutoTuneEnabled(Out<bool> out_enabled) {
+    *out_enabled = false;
+    LOG_DEBUG(Service_Audio, "(STUBBED) IsAudioDeviceOutputVolumeAutoTuneEnabled called. returning false");
+    R_SUCCEED();
+}
+
 } // namespace Service::Audio

src/core/hle/service/audio/audio_device.h

@@ -1,3 +1,6 @@
+// SPDX-FileCopyrightText: Copyright 2025 Eden Emulator Project
+// SPDX-License-Identifier: GPL-3.0-or-later
+
 // SPDX-FileCopyrightText: Copyright 2024 yuzu Emulator Project
 // SPDX-License-Identifier: GPL-2.0-or-later
 
@@ -49,6 +52,13 @@ private:
     Result ListAudioOutputDeviceName(
         OutArray<AudioDevice::AudioDeviceName, BufferAttr_HipcMapAlias> out_names,
         Out<s32> out_count);
+    Result AcquireAudioInputDeviceNotification(OutCopyHandle<Kernel::KEvent> out_event_handle, u64 device_id);
+    Result ReleaseAudioInputDeviceNotification(u64 device_id);
+    Result AcquireAudioOutputDeviceNotification(OutCopyHandle<Kernel::KEvent> out_event_handle, u64 device_id);
+    Result ReleaseAudioOutputDeviceNotification(u64 device_id);
+    Result SetAudioDeviceOutputVolumeAutoTuneEnabled(bool enabled);
+    Result IsAudioDeviceOutputVolumeAutoTuneEnabled(Out<bool> out_enabled);
+
 
     KernelHelpers::ServiceContext service_context;
     std::unique_ptr<AudioCore::Renderer::AudioDevice> impl;