UE5.7 Quest 3S standalone - AudioMixerPlatformInterface Timeout, no microphone input

What do you need help with?

Question

Installation method

Not sure

Issue area

Microphone / Voice Input

Impact

Blocker - I cannot continue

Unreal Engine version

UE 5.7.4

Convai Unreal Engine Plugin version

Using Convai plugin 4.0.0-beta.21, UE 5.7.4, Meta Quest 3S standalone build.

Project setup

Blueprint

Target platform

Meta quest3s

Where does it happen?

Only after packaging

Short summary

Character appears in VR, session connects successfully, but microphone input never works.

What happened?

Hello,

Using Convai plugin 4.0.0-beta.21, UE 5.7.4, Meta Quest 3S standalone build.

Character appears in VR, session connects successfully, but microphone input never works.

ADB logcat shows:

  • Session starts successfully
  • OnConnectedToServer called
  • But: “ConvaiPlayerLog: Stopped default audio capture”
  • “AudioMixerPlatformInterface Timeout [5 Seconds] waiting for h/w”

RECORD_AUDIO permission enabled. Push to Talk disabled. Mobile Mode enabled. BP_VRSpectator parent class set to Pawn.

What is the correct setup for microphone capture on Quest 3S standalone?

What did you expect?

TELL ME HOW İ CAN FİX İT

I checked the relevant documentation, resources, and similar forum posts before posting.

on

I confirm that I did not include API keys, tokens, passwords, secrets, private character data, private conversation logs, or customer data.

on

Hello,

Welcome to the Convai Developer Forum!

Could you please share the logs?

Also, did you test this in the Playground? Does STT work correctly there?

Hello,

Thank you for the quick response!

Playground test: Yes, STT works correctly in the Playground. Character responds to voice input perfectly there.

ADB Logcat:

ConvaiChatbotComponentLog: Auto Initializing Session
ConvaiConnectionManagerLog: Character [778994e8-5f7a-11f1-b5fb-42010a7be02e]: Establishing new connection
ConvaiChatbotComponentLog: Session started for character ID: 778994e8-5f7a-11f1-b5fb-42010a7be02e
ConvaiConnectionManagerLog: Warning: Cannot acquire connection - another component already owns the active connection
LogBlueprintUserMessages: [BP_ConvaiPlayerComponent] Owner is invalid: Make sure the owner of ConvaiPlayerComponent is a Pawn.
ConvaiPlayerLog: Stopped default audio capture
LogAudioMixer: Warning: AudioMixerPlatformInterface Timeout [5 Seconds] waiting for h/w. InstanceID=1
ConvaiSubsystemLog: OnConnectedToServer called SessionID: bc420cb3...

Setup:

  • UE 5.7.4, Convai plugin 4.0.0-beta.21
  • Meta Quest 3S standalone build
  • BP_ConvaiPlayerComponent added to BP_VRSpectator (parent class: Pawn)
  • ConvaiChatbotComponent added to MetaHuman BP_Lexi
  • RECORD_AUDIO permission enabled
  • Push to Talk disabled, Mobile Mode enabled

Main issue: AudioMixerPlatformInterface Timeout - audio hardware never initializes, so microphone capture cannot start.

Could you please test this directly in the Unreal Engine Editor, rather than in the packaged build?

It works in the Editor! When I press Play in Unreal Engine Editor, the character responds to voice input correctly.

But in the packaged standalone build on Meta Quest 3S, microphone input does not work. The ADB logcat shows “AudioMixerPlatformInterface Timeout” in the packaged build.

What configuration is needed to make microphone work in the packaged Android/Quest standalone build?

Since it works correctly in the Unreal Engine Editor, this is most likely related to microphone permissions or Android/Quest build configuration rather than Convai itself.

Please check the microphone permissions on the Quest 3S and make sure the packaged app has permission to access the microphone.

I’d also recommend checking Unreal Engine / Meta Quest documentation, or using AI assistants to look into Unreal Engine Quest 3 microphone permission Android packaged build, as this is likely related to the platform permission setup.

Microphone permission is granted on Quest 3S for the app.

RECORD_AUDIO, MODIFY_AUDIO_SETTINGS and CAPTURE_AUDIO_OUTPUT permissions are all added in Advanced APK Packaging.

The issue persists - microphone still not working in packaged build. ADB logcat shows no audio or Convai related logs when speaking.

Key observation:

  • Works perfectly in UE Editor (PC)
  • Does NOT work in packaged Quest 3S standalone APK
  • No Convai logs appear at all in logcat when app is running on Quest

Is there a specific Android audio configuration or ConvaiPlayerComponent setup required for Quest standalone builds with Convai 4.0.0-beta.21?

Hi! Since voice works in the Unreal Editor but not on the Quest standalone build, this is almost certainly an Android microphone permission issue — not a Convai bug.

On Quest, the app must ask for microphone permission at runtime before any voice input can work.

Here is a simple setup you can try:


Step 1 — Enable the Android Permission plugin

  1. In Unreal Editor, go to Edit > Plugins
  2. Search for Android Permission
  3. Make sure it is Enabled
  4. Restart the editor if prompted

Step 2 — Add the permission to your Android build settings

  1. Go to Edit > Project Settings

  2. Open Platforms > Android > Advanced APK Packaging

  3. Find Extra Permissions

  4. Click + and add:

    android.permission.RECORD_AUDIO

  5. Save and close Project Settings


Step 3 — Create a Blueprint that asks for permission when the game starts

The easiest place is your GameMode Blueprint (or your Player Controller if you prefer).

  1. Open your GameMode Blueprint (for example VRGameMode if you use the VR Template)
  2. In the Event Graph, add Event BeginPlay
  3. Add a Delay node (about 0.5–1.0 seconds) after BeginPlay
    → Some projects crash if permissions are requested immediately on startup; a short delay avoids that.
  4. After the Delay, right-click and search for Check Android Permission
    • Permission input: android.permission.RECORD_AUDIO
  5. Add a Branch node:
    • If true → permission is already granted, you are done
    • If false → continue below
  6. Create a String Array variable (name it Permissions)
    • Add one entry: android.permission.RECORD_AUDIO
  7. Add Request Android Permissions
    • Connect your Permissions array to the input
  8. From the Return Value pin of Request Android Permissions, drag out and choose Assign On Permissions Granted (or similar delegate bind)
  9. In that callback, check that android.permission.RECORD_AUDIO was granted
    • If granted → your app can now use the microphone
    • If denied → show a message telling the user to enable Microphone in Quest Settings

Blueprint flow (simplified):

Event BeginPlay
→ Delay (0.5s)
→ Check Android Permission (android.permission.RECORD_AUDIO)
→ Branch
→ True: done
→ False: Request Android Permissions ([android.permission.RECORD_AUDIO])
→ On Permissions Granted: continue game / start Convai voice


Step 4 — Rebuild and redeploy

After adding the Blueprint above:

  1. Package your project again for Android / Quest
  2. Install the new APK on the Quest
  3. On first launch you should see an Android microphone permission popup
  4. Tap Allow

If you previously denied it:

  • On Quest: Settings > Apps > [Your App] > Permissions > Microphone → Allow

Step 5 — Test again

After permission is granted, try your Convai voice input again on the standalone build.

If it still fails, please share:

  1. Did the permission popup appear on first launch? (yes/no)

  2. Is Microphone enabled in Quest app permissions?

  3. Android log output:

    adb logcat -s ConvaiAudioLog:V LogConvai:V


Official references

Let us know how it goes after Step 4 — especially whether the permission popup appears.