diff --git a/CHANGELOG.md b/CHANGELOG.md
index 5af25c30e43..92ce72e694c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -15,6 +15,7 @@ Docs: https://docs.openclaw.ai
 
 ### Fixes
 
+- macOS/Voice input: guard all audio-input startup paths against missing default microphones (Voice Wake, Talk Mode, Push-to-Talk, mic-level monitor, tester) to avoid launch/runtime crashes on mic-less Macs and fail gracefully until input becomes available. (#25817) Thanks @sfo2001.
 - Gateway/Security: enforce gateway auth for the exact `/api/channels` plugin root path (plus `/api/channels/` descendants), with regression coverage for query/trailing-slash variants and near-miss paths that must remain plugin-owned. (#25753) Thanks @bmendonca3.
 - Security/Exec: sanitize inherited host execution environment before merge, canonicalize inherited PATH handling, and strip dangerous keys (`LD_*`, `DYLD_*`, `SSLKEYLOGFILE`, and related injection vectors) from non-sandboxed exec runs. (#25755) Thanks @bmendonca3.
 - Security/Hooks: normalize hook session-key classification with trim/lowercase plus Unicode NFKC folding (for example full-width `ＨＯＯＫ：...`) so external-content wrapping cannot be bypassed by mixed-case or lookalike prefixes. (#25750) Thanks @bmendonca3.
diff --git a/apps/macos/Sources/OpenClaw/AudioInputDeviceObserver.swift b/apps/macos/Sources/OpenClaw/AudioInputDeviceObserver.swift
index abbddb24588..6c01628144b 100644
--- a/apps/macos/Sources/OpenClaw/AudioInputDeviceObserver.swift
+++ b/apps/macos/Sources/OpenClaw/AudioInputDeviceObserver.swift
@@ -53,6 +53,15 @@ final class AudioInputDeviceObserver {
         return output
     }
 
+    /// Returns true when the system default input device exists and is alive with input channels.
+    /// Use this preflight before accessing `AVAudioEngine.inputNode` to avoid SIGABRT on Macs
+    /// without a built-in microphone (Mac mini, Mac Pro, Mac Studio) or when an external mic
+    /// is disconnected.
+    static func hasUsableDefaultInputDevice() -> Bool {
+        guard let uid = self.defaultInputDeviceUID() else { return false }
+        return self.aliveInputDeviceUIDs().contains(uid)
+    }
+
     static func defaultInputDeviceSummary() -> String {
         let systemObject = AudioObjectID(kAudioObjectSystemObject)
         var address = AudioObjectPropertyAddress(
diff --git a/apps/macos/Sources/OpenClaw/MicLevelMonitor.swift b/apps/macos/Sources/OpenClaw/MicLevelMonitor.swift
index e35057d28cf..81e06abda2d 100644
--- a/apps/macos/Sources/OpenClaw/MicLevelMonitor.swift
+++ b/apps/macos/Sources/OpenClaw/MicLevelMonitor.swift
@@ -14,6 +14,13 @@ actor MicLevelMonitor {
         if self.running { return }
         self.logger.info(
             "mic level monitor start (\(AudioInputDeviceObserver.defaultInputDeviceSummary(), privacy: .public))")
+        guard AudioInputDeviceObserver.hasUsableDefaultInputDevice() else {
+            self.engine = nil
+            throw NSError(
+                domain: "MicLevelMonitor",
+                code: 1,
+                userInfo: [NSLocalizedDescriptionKey: "No usable audio input device available"])
+        }
         let engine = AVAudioEngine()
         self.engine = engine
         let input = engine.inputNode
diff --git a/apps/macos/Sources/OpenClaw/TalkModeRuntime.swift b/apps/macos/Sources/OpenClaw/TalkModeRuntime.swift
index 443bc192295..70184ce9cc7 100644
--- a/apps/macos/Sources/OpenClaw/TalkModeRuntime.swift
+++ b/apps/macos/Sources/OpenClaw/TalkModeRuntime.swift
@@ -185,6 +185,12 @@ actor TalkModeRuntime {
         }
         guard let audioEngine = self.audioEngine else { return }
 
+        guard AudioInputDeviceObserver.hasUsableDefaultInputDevice() else {
+            self.audioEngine = nil
+            self.logger.error("talk mode: no usable audio input device")
+            return
+        }
+
         let input = audioEngine.inputNode
         let format = input.outputFormat(forBus: 0)
         input.removeTap(onBus: 0)
diff --git a/apps/macos/Sources/OpenClaw/VoicePushToTalk.swift b/apps/macos/Sources/OpenClaw/VoicePushToTalk.swift
index e535ebd6616..6eaa45e0675 100644
--- a/apps/macos/Sources/OpenClaw/VoicePushToTalk.swift
+++ b/apps/macos/Sources/OpenClaw/VoicePushToTalk.swift
@@ -244,6 +244,14 @@ actor VoicePushToTalk {
         }
         guard let audioEngine = self.audioEngine else { return }
 
+        guard AudioInputDeviceObserver.hasUsableDefaultInputDevice() else {
+            self.audioEngine = nil
+            throw NSError(
+                domain: "VoicePushToTalk",
+                code: 1,
+                userInfo: [NSLocalizedDescriptionKey: "No usable audio input device available"])
+        }
+
         let input = audioEngine.inputNode
         let format = input.outputFormat(forBus: 0)
         if self.tapInstalled {
diff --git a/apps/macos/Sources/OpenClaw/VoiceWakeRuntime.swift b/apps/macos/Sources/OpenClaw/VoiceWakeRuntime.swift
index 61f913b9da8..b7e2d329b82 100644
--- a/apps/macos/Sources/OpenClaw/VoiceWakeRuntime.swift
+++ b/apps/macos/Sources/OpenClaw/VoiceWakeRuntime.swift
@@ -166,6 +166,14 @@ actor VoiceWakeRuntime {
             }
             guard let audioEngine = self.audioEngine else { return }
 
+            guard AudioInputDeviceObserver.hasUsableDefaultInputDevice() else {
+                self.audioEngine = nil
+                throw NSError(
+                    domain: "VoiceWakeRuntime",
+                    code: 1,
+                    userInfo: [NSLocalizedDescriptionKey: "No usable audio input device available"])
+            }
+
             let input = audioEngine.inputNode
             let format = input.outputFormat(forBus: 0)
             guard format.channelCount > 0, format.sampleRate > 0 else {
diff --git a/apps/macos/Sources/OpenClaw/VoiceWakeTester.swift b/apps/macos/Sources/OpenClaw/VoiceWakeTester.swift
index b3d0c58d90c..063fea826ab 100644
--- a/apps/macos/Sources/OpenClaw/VoiceWakeTester.swift
+++ b/apps/macos/Sources/OpenClaw/VoiceWakeTester.swift
@@ -89,6 +89,14 @@ final class VoiceWakeTester {
         self.logInputSelection(preferredMicID: micID)
         self.configureSession(preferredMicID: micID)
 
+        guard AudioInputDeviceObserver.hasUsableDefaultInputDevice() else {
+            self.audioEngine = nil
+            throw NSError(
+                domain: "VoiceWakeTester",
+                code: 1,
+                userInfo: [NSLocalizedDescriptionKey: "No usable audio input device available"])
+        }
+
         let engine = AVAudioEngine()
         self.audioEngine = engine
 
diff --git a/apps/macos/Tests/OpenClawIPCTests/AudioInputDeviceObserverTests.swift b/apps/macos/Tests/OpenClawIPCTests/AudioInputDeviceObserverTests.swift
new file mode 100644
index 00000000000..a175e5e1a0a
--- /dev/null
+++ b/apps/macos/Tests/OpenClawIPCTests/AudioInputDeviceObserverTests.swift
@@ -0,0 +1,21 @@
+import Foundation
+import Testing
+@testable import OpenClaw
+
+@Suite struct AudioInputDeviceObserverTests {
+    @Test func hasUsableDefaultInputDeviceReturnsBool() {
+        // Smoke test: verifies the composition logic runs without crashing.
+        // Actual result depends on whether the host has an audio input device.
+        let result = AudioInputDeviceObserver.hasUsableDefaultInputDevice()
+        _ = result // suppress unused-variable warning; the assertion is "no crash"
+    }
+
+    @Test func hasUsableDefaultInputDeviceConsistentWithComponents() {
+        // When no default UID exists, the method must return false.
+        // When a default UID exists, the result must match alive-set membership.
+        let uid = AudioInputDeviceObserver.defaultInputDeviceUID()
+        let alive = AudioInputDeviceObserver.aliveInputDeviceUIDs()
+        let expected = uid.map { alive.contains($0) } ?? false
+        #expect(AudioInputDeviceObserver.hasUsableDefaultInputDevice() == expected)
+    }
+}