Fix aggregate device volume slider permanently broken after install

BGMApp/BGMApp/BGMAudioDevice.cpp

@@ -72,6 +72,20 @@ bool    BGMAudioDevice::CanBeOutputDeviceInBGMApp() const
             canBeDefault;
 }
 
+#pragma mark Device Type
+
+bool    BGMAudioDevice::IsAggregate() const
+{
+    try
+    {
+        return GetTransportType() == kAudioDeviceTransportTypeAggregate;
+    }
+    catch(CAException)
+    {
+        return false;
+    }
+}
+
 #pragma mark Available Controls
 
 bool    BGMAudioDevice::HasSettableMasterVolume(AudioObjectPropertyScope inScope) const
@@ -115,6 +129,12 @@ bool    BGMAudioDevice::HasSettableMasterMute(AudioObjectPropertyScope inScope)
 void    BGMAudioDevice::CopyMuteFrom(const BGMAudioDevice inDevice,
                                      AudioObjectPropertyScope inScope)
 {
+    // Skip aggregate devices for the same reason as in CopyVolumeFrom.
+    if(IsAggregate() || inDevice.IsAggregate())
+    {
+        return;
+    }
+
     // TODO: Support for devices that have per-channel mute controls but no master mute control
     if(HasSettableMasterMute(inScope) && inDevice.HasMuteControl(inScope, kMasterChannel))
     {
@@ -127,6 +147,17 @@ void    BGMAudioDevice::CopyMuteFrom(const BGMAudioDevice inDevice,
 void    BGMAudioDevice::CopyVolumeFrom(const BGMAudioDevice inDevice,
                                        AudioObjectPropertyScope inScope)
 {
+    // Don't try to copy volume to/from aggregate devices. Aggregate devices rely on macOS to
+    // manage their virtual volume control through the sub-devices. Using the deprecated
+    // AudioHardwareService APIs (which we use for virtual master volume) to write to an aggregate
+    // device can corrupt its volume control state, causing the volume slider to become permanently
+    // disabled in System Settings. See https://github.com/kyleneideck/BackgroundMusic/issues/848
+    if(IsAggregate() || inDevice.IsAggregate())
+    {
+        DebugMsg("BGMAudioDevice::CopyVolumeFrom: Skipping volume copy for aggregate device");
+        return;
+    }
+
     // Get the volume of the other device.
     bool didGetVolume = false;
     Float32 volume = FLT_MIN;
@@ -155,7 +186,7 @@ void    BGMAudioDevice::CopyVolumeFrom(const BGMAudioDevice inDevice,
 
         if(numChannels > 0)  // Avoid divide by zero.
         {
-            volume /= numChannels;
+            volume /= static_cast<Float32>(numChannels);
         }
     }
 

BGMApp/BGMApp/BGMAudioDevice.h

@@ -78,6 +78,14 @@ class BGMAudioDevice
      */
     bool               CanBeOutputDeviceInBGMApp() const;
 
+#pragma mark Device Type
+
+    /*!
+     @return True if this device is an aggregate device (i.e. a device created in Audio MIDI Setup
+             that combines multiple audio devices).
+     */
+    bool               IsAggregate() const;
+
 #pragma mark Available Controls
 
     bool               HasSettableMasterVolume(AudioObjectPropertyScope inScope) const;

BGMApp/BGMApp/BGMAutoPauseMusic.mm

@@ -206,7 +206,7 @@ - (void) queueUnpauseBlock {
     // TODO: Fading in and out would make short pauses a lot less jarring because, if they were short enough, we wouldn't
     //       actually pause the music player. So you'd hear a dip in the music's volume rather than a gap.
     UInt64 unpauseDelayNsec =
-        static_cast<UInt64>((wentSilent - wentAudible) * kUnpauseDelayWeightingFactor);
+        static_cast<UInt64>(static_cast<Float64>(wentSilent - wentAudible) * kUnpauseDelayWeightingFactor);
 
     // Convert from absolute time to nanos.
     mach_timebase_info_data_t info;

BGMApp/BGMApp/BGMDeviceControlsList.cpp

@@ -186,9 +186,21 @@ bool    BGMDeviceControlsList::MatchControlsListOf(AudioObjectID inDeviceID)
 
     // Check which controls the other device has.
     BGMAudioDevice device(inDeviceID);
-    bool hasMute = device.HasSettableMasterMute(inScope);
 
-    bool hasVolume =
+    // Aggregate devices (created in Audio MIDI Setup) rely on macOS to provide virtual volume
+    // control through the sub-devices. The deprecated AudioHardwareService APIs we use to detect
+    // volume support can return incorrect results for aggregate devices on newer macOS versions,
+    // which causes us to incorrectly disable BGMDevice's volume control. This then triggers
+    // PropagateControlListChange (which toggles the default device through a null device), and
+    // that can permanently break the aggregate device's volume slider in System Settings.
+    //
+    // To avoid this, always report that aggregate devices have volume and mute controls, since
+    // macOS provides virtual volume/mute for them regardless of what the HAL reports.
+    bool isAggregate = device.IsAggregate();
+
+    bool hasMute = isAggregate || device.HasSettableMasterMute(inScope);
+
+    bool hasVolume = isAggregate ||
         device.HasSettableMasterVolume(inScope) || device.HasSettableVirtualMasterVolume(inScope);
 
     if(!hasVolume)

BGMApp/BGMApp/BGMPlayThrough.cpp

@@ -606,8 +606,8 @@ OSStatus    BGMPlayThrough::WaitForOutputDeviceToStart() noexcept
 
         DebugMsg("BGMPlayThrough::WaitForOutputDeviceToStart: Started %f ms after notification, %f "
                  "ms after entering WaitForOutputDeviceToStart.",
-                 static_cast<Float64>(startedBy - mToldOutputDeviceToStartAt) * base / NSEC_PER_MSEC,
-                 static_cast<Float64>(startedBy - startedAt) * base / NSEC_PER_MSEC);
+                 static_cast<Float64>(startedBy - mToldOutputDeviceToStartAt) * static_cast<Float64>(base) / NSEC_PER_MSEC,
+                 static_cast<Float64>(startedBy - startedAt) * static_cast<Float64>(base) / NSEC_PER_MSEC);
     }
 
     // Figure out which error code to return.
@@ -1121,7 +1121,7 @@ OSStatus    BGMPlayThrough::OutputDeviceIOProc(AudioObjectID           inDevice,
                                                 refCon->mInToOutSampleOffset);
 
             // Recalculate the in-to-out offset and read head.
-            refCon->mInToOutSampleOffset = inOutputTime->mSampleTime - lastInputSampleTime;
+            refCon->mInToOutSampleOffset = inOutputTime->mSampleTime - static_cast<Float64>(lastInputSampleTime);
             readHeadSampleTime = static_cast<CARingBuffer::SampleTime>(
                     inOutputTime->mSampleTime - refCon->mInToOutSampleOffset);
         }

BGMDriver/BGMDriver/BGM_Device.cpp

@@ -1361,8 +1361,8 @@ void	BGM_Device::GetZeroTimeStamp(Float64& outSampleTime, UInt64& outHostTime, U
     	}
 
     	//	set the return values
-    	outSampleTime = mLoopbackTime.numberTimeStamps * kLoopbackRingBufferFrameSize;
-    	outHostTime = static_cast<UInt64>(mLoopbackTime.anchorHostTime + (static_cast<Float64>(mLoopbackTime.numberTimeStamps) * theHostTicksPerRingBuffer));
+    	outSampleTime = static_cast<Float64>(mLoopbackTime.numberTimeStamps) * kLoopbackRingBufferFrameSize;
+    	outHostTime = static_cast<UInt64>(static_cast<Float64>(mLoopbackTime.anchorHostTime) + (static_cast<Float64>(mLoopbackTime.numberTimeStamps) * theHostTicksPerRingBuffer));
         // TODO: I think we should increment outSeed whenever this device switches to/from having a wrapped engine
     	outSeed = 1;
     }
@@ -1523,16 +1523,13 @@ void	BGM_Device::EndIOOperation(UInt32 inOperationID, UInt32 inIOBufferFrameSize
 void	BGM_Device::ReadInputData(UInt32 inIOBufferFrameSize, Float64 inSampleTime, void* outBuffer)
 {
     // Wrap the provided buffer in an AudioBufferList.
-    AudioBufferList abl = {
-        .mNumberBuffers = 1,
-        .mBuffers[0] = {
-            .mNumberChannels = 2,
-            // Each frame is 2 Float32 samples (one per channel). The number of frames * the number
-            // of bytes per frame = the size of outBuffer in bytes.
-            .mDataByteSize = static_cast<UInt32>(inIOBufferFrameSize * sizeof(Float32) * 2),
-            .mData = outBuffer
-        }
-    };
+    AudioBufferList abl;
+    abl.mNumberBuffers = 1;
+    abl.mBuffers[0].mNumberChannels = 2;
+    // Each frame is 2 Float32 samples (one per channel). The number of frames * the number
+    // of bytes per frame = the size of outBuffer in bytes.
+    abl.mBuffers[0].mDataByteSize = static_cast<UInt32>(inIOBufferFrameSize * sizeof(Float32) * 2);
+    abl.mBuffers[0].mData = outBuffer;
 
     // Copy the audio data from our ring buffer into the provided buffer.
     CARingBufferError err =
@@ -1562,16 +1559,13 @@ void	BGM_Device::ReadInputData(UInt32 inIOBufferFrameSize, Float64 inSampleTime,
 void	BGM_Device::WriteOutputData(UInt32 inIOBufferFrameSize, Float64 inSampleTime, const void* inBuffer)
 {
     // Wrap the provided buffer in an AudioBufferList.
-    AudioBufferList abl = {
-        .mNumberBuffers = 1,
-        .mBuffers[0] = {
-            .mNumberChannels = 2,
-            // Each frame is 2 Float32 samples (one per channel). The number of frames * the number
-            // of bytes per frame = the size of inBuffer in bytes.
-            .mDataByteSize = static_cast<UInt32>(inIOBufferFrameSize * sizeof(Float32) * 2),
-            .mData = const_cast<void *>(inBuffer)
-        }
-    };
+    AudioBufferList abl;
+    abl.mNumberBuffers = 1;
+    abl.mBuffers[0].mNumberChannels = 2;
+    // Each frame is 2 Float32 samples (one per channel). The number of frames * the number
+    // of bytes per frame = the size of inBuffer in bytes.
+    abl.mBuffers[0].mDataByteSize = static_cast<UInt32>(inIOBufferFrameSize * sizeof(Float32) * 2);
+    abl.mBuffers[0].mData = const_cast<void *>(inBuffer);
 
     // Copy the audio data from the provided buffer into our ring buffer.
     CARingBufferError err =
@@ -1908,7 +1902,7 @@ Float64	BGM_Device::_HW_GetSampleRate() const
             CAException(kAudioHardwareUnspecifiedError),
             "BGM_Device::_HW_GetSampleRate: No wrapped audio device");
 
-    return mWrappedAudioEngine->GetSampleRate();
+    return static_cast<Float64>(mWrappedAudioEngine->GetSampleRate());
 }
 
 kern_return_t	BGM_Device::_HW_SetSampleRate(Float64 inNewSampleRate)

BGMDriver/BGMDriver/BGM_NullDevice.cpp

@@ -471,8 +471,8 @@ void    BGM_NullDevice::GetZeroTimeStamp(Float64& outSampleTime,
         (static_cast<Float64>(mNumberTimeStamps) * theHostTicksPerPeriod);
 
     // Set the return values.
-    outSampleTime = mNumberTimeStamps * kZeroTimeStampPeriod;
-    outHostTime = static_cast<UInt64>(mAnchorHostTime + theHostTicksSinceAnchor);
+    outSampleTime = static_cast<Float64>(mNumberTimeStamps) * kZeroTimeStampPeriod;
+    outHostTime = static_cast<UInt64>(static_cast<Float64>(mAnchorHostTime) + theHostTicksSinceAnchor);
     outSeed = 1;
 }
 

BGMDriver/BGMDriver/BGM_VolumeControl.cpp

@@ -440,7 +440,7 @@ void    BGM_VolumeControl::SetVolumeRaw(SInt32 inNewVolumeRaw)
         // TODO: This assumes the control should never boost the signal. (So, technically, it never
         //       actually applies gain, only loss.)
         SInt32 theRawRange = mMaxVolumeRaw - mMinVolumeRaw;
-        SInt32 theSliderPositionInRawSteps = static_cast<SInt32>(theSliderPosition * theRawRange);
+        SInt32 theSliderPositionInRawSteps = static_cast<SInt32>(theSliderPosition * static_cast<Float32>(theRawRange));
         theSliderPositionInRawSteps += mMinVolumeRaw;
 
         mAmplitudeGain = mVolumeCurve.ConvertRawToScalar(theSliderPositionInRawSteps);

BGMDriver/PublicUtility/CAVolumeCurve.cpp

@@ -400,7 +400,7 @@ Float32	CAVolumeCurve::ConvertRawToDB(SInt32 inRaw) const
 		SInt32 theRawStepsToAdd = std::min(theRawRange, theNumberRawSteps);
 
 		//	add this many steps worth of db to the answer;
-		theAnswer += theRawStepsToAdd * theDBPerRaw;
+		theAnswer += static_cast<Float32>(theRawStepsToAdd) * theDBPerRaw;
 
 		//	figure out how many steps are left
 		theNumberRawSteps -= theRawStepsToAdd;