diff --git a/app/xcode/Package.swift b/app/xcode/Package.swift
index e631697..2075c37 100644
--- a/app/xcode/Package.swift
+++ b/app/xcode/Package.swift
@@ -25,7 +25,7 @@ let package = Package(
         .target(name: "VCamUIFoundation"),
         .target(name: "VCamData", dependencies: ["VCamEntity"]),
         .target(name: "VCamEntity", dependencies: ["VCamDefaults", "VCamLocalization"], swiftSettings: [
-//            .define("ENABLE_MOCOPI")
+            .define("ENABLE_MOCOPI")
         ]),
         .target(name: "VCamLocalization", resources: [.process("VCamResources")]),
         .target(name: "VCamMedia", dependencies: ["VCamEntity", "VCamAppExtension"]),
diff --git a/app/xcode/Sources/VCamEntity/AudioDevice.swift b/app/xcode/Sources/VCamEntity/AudioDevice.swift
new file mode 100644
index 0000000..f068f5f
--- /dev/null
+++ b/app/xcode/Sources/VCamEntity/AudioDevice.swift
@@ -0,0 +1,19 @@
+//
+//  AudioDevice.swift
+//  
+//
+//  Created by Tatsuya Tanaka on 2022/04/24.
+//
+
+import Foundation
+import struct AVFAudio.AudioDeviceID
+
+public struct AudioDevice: Hashable, Identifiable {
+    public init(id: AudioDeviceID, uid: String) {
+        self.id = id
+        self.uid = uid
+    }
+
+    public let id: AudioDeviceID
+    public let uid: String
+}
diff --git a/app/xcode/Sources/VCamMedia/AudioDevice+.swift b/app/xcode/Sources/VCamMedia/AudioDevice+.swift
new file mode 100644
index 0000000..f43dfcf
--- /dev/null
+++ b/app/xcode/Sources/VCamMedia/AudioDevice+.swift
@@ -0,0 +1,147 @@
+//
+//  AudioDevice+.swift
+//  
+//
+//  Created by Tatsuya Tanaka on 2022/04/24.
+//
+
+import Foundation
+import CoreAudio
+import VCamEntity
+
+extension AudioDevice {
+    public init(id: AudioDeviceID) {
+        self.init(id: id, uid: Self.getUid(id: id))
+    }
+
+    private static func getUid(id: AudioDeviceID) -> String {
+        var address = AudioObjectPropertyAddress(
+            mSelector: AudioObjectPropertySelector(kAudioDevicePropertyDeviceUID),
+            mScope: AudioObjectPropertyScope(kAudioObjectPropertyScopeGlobal),
+            mElement: AudioObjectPropertyElement(kAudioObjectPropertyElementMain)
+        )
+
+        var name: CFString?
+        var propsize: UInt32 = UInt32(MemoryLayout<CFString?>.size)
+        let result: OSStatus = AudioObjectGetPropertyData(id, &address, 0, nil, &propsize, &name)
+        if result != 0 {
+            return ""
+        }
+
+        if let str = name {
+            return str as String
+        }
+
+        return ""
+    }
+}
+
+public extension AudioDevice {
+    static func defaultDevice() -> AudioDevice? {
+        var outputID: AudioDeviceID = 0
+        var propsize = UInt32(MemoryLayout<AudioDeviceID>.size)
+        var address = AudioObjectPropertyAddress(
+            mSelector: kAudioHardwarePropertyDefaultInputDevice,
+            mScope: kAudioObjectPropertyScopeGlobal,
+            mElement: kAudioObjectPropertyElementMain
+        )
+        let error = AudioObjectGetPropertyData(AudioObjectID(kAudioObjectSystemObject),
+                                               &address,
+                                               0,
+                                               nil,
+                                               &propsize,
+                                               &outputID)
+        if error != noErr {
+            print("defaultDevice error: \(error)")
+            return nil
+        }
+        return AudioDevice(id: outputID)
+    }
+
+    func name() -> String {
+        var address = AudioObjectPropertyAddress(
+            mSelector: AudioObjectPropertySelector(kAudioDevicePropertyDeviceNameCFString),
+            mScope: AudioObjectPropertyScope(kAudioObjectPropertyScopeGlobal),
+            mElement: AudioObjectPropertyElement(kAudioObjectPropertyElementMain)
+        )
+
+        var name: CFString?
+        var propsize: UInt32 = UInt32(MemoryLayout<CFString?>.size)
+        let result: OSStatus = AudioObjectGetPropertyData(id, &address, 0, nil, &propsize, &name)
+        if result != 0 {
+            return ""
+        }
+
+        let value = name as? String ?? ""
+        return value
+//        return value.hasPrefix("CADefaultDevice") ? L10n.default.text : value
+    }
+
+    func bufferSize() -> UInt32 {
+        var address =  AudioObjectPropertyAddress(mSelector: kAudioDevicePropertyAvailableNominalSampleRates, mScope: kAudioObjectPropertyScopeGlobal, mElement: kAudioObjectPropertyElementMain)
+        var buf: UInt32 = 0
+        var bufSize = UInt32(MemoryLayout<UInt32>.size)
+
+        AudioObjectGetPropertyData(id, &address, 0, nil, &bufSize, &buf)
+        return buf
+    }
+
+    func sampleRate() -> Float64 {
+        var address =  AudioObjectPropertyAddress(mSelector: kAudioDevicePropertyActualSampleRate, mScope: kAudioObjectPropertyScopeGlobal, mElement: kAudioObjectPropertyElementMain)
+        var buf: Float64 = 0
+        var bufSize = UInt32(MemoryLayout<Float64>.size)
+
+        AudioObjectGetPropertyData(id, &address, 0, nil, &bufSize, &buf)
+        return buf
+    }
+
+    func latencyTimeInterval() -> TimeInterval {
+        let sampleRate = sampleRate()
+        guard sampleRate > 0 else {
+            return 0
+        }
+
+        return TimeInterval(
+            safetyOffset(scope: kAudioObjectPropertyScopeInput) +
+            bufferFrameSize(scope: kAudioObjectPropertyScopeInput) +
+            safetyOffset(scope: kAudioObjectPropertyScopeOutput) +
+            bufferFrameSize(scope: kAudioObjectPropertyScopeOutput)
+        ) / sampleRate
+    }
+
+    private func deviceLatency(scope: AudioObjectPropertyScope) -> UInt32 {
+        var address =  AudioObjectPropertyAddress(mSelector: kAudioDevicePropertyLatency, mScope: scope, mElement: kAudioObjectPropertyElementMain)
+        var buf: UInt32 = 0
+        var bufSize = UInt32(MemoryLayout<UInt32>.size)
+
+        _ = AudioObjectGetPropertyData(id, &address, 0, nil, &bufSize, &buf)
+        return buf
+    }
+
+    private func streamLatency(scope: AudioObjectPropertyScope) -> UInt32 {
+        var address =  AudioObjectPropertyAddress(mSelector: kAudioStreamPropertyLatency, mScope: scope, mElement: kAudioObjectPropertyElementMain)
+        var buf: UInt32 = 0
+        var bufSize = UInt32(MemoryLayout<UInt32>.size)
+
+        _ = AudioObjectGetPropertyData(id, &address, 0, nil, &bufSize, &buf)
+        return buf
+    }
+
+    private func safetyOffset(scope: AudioObjectPropertyScope) -> UInt32 {
+        var address =  AudioObjectPropertyAddress(mSelector: kAudioDevicePropertySafetyOffset, mScope: scope, mElement: kAudioObjectPropertyElementMain)
+        var buf: UInt32 = 0
+        var bufSize = UInt32(MemoryLayout<UInt32>.size)
+
+        _ = AudioObjectGetPropertyData(id, &address, 0, nil, &bufSize, &buf)
+        return buf
+    }
+
+    private func bufferFrameSize(scope: AudioObjectPropertyScope) -> UInt32 {
+        var address =  AudioObjectPropertyAddress(mSelector: kAudioDevicePropertyBufferFrameSize, mScope: scope, mElement: kAudioObjectPropertyElementMain)
+        var buf: UInt32 = 0
+        var bufSize = UInt32(MemoryLayout<UInt32>.size)
+
+        _ = AudioObjectGetPropertyData(id, &address, 0, nil, &bufSize, &buf)
+        return buf
+    }
+}