Voice Events

VoiceConnection exposes async events for user activity, audio frames, packet diagnostics, and DAVE state.

Event List

Event	Args	Purpose
UserSpeaking	UserSpeakingEventArgs	Discord speaking flag updates (OP5)
UserJoined	VoiceUserJoinEventArgs	User SSRC/user binding joined
UserLeft	VoiceUserLeaveEventArgs	User SSRC/user binding left
VoiceReceived	VoiceReceiveEventArgs	Decoded PCM (and source Opus when available)
VoicePacketDropped	VoicePacketDroppedEventArgs	Inbound packet drop classification
DaveStateChanged	DaveStateChangedEventArgs	DAVE control-plane transitions with executing sender status
DaveOpcodeObserved	DaveOpcodeEventArgs	DAVE opcode send/receive diagnostics
VoiceSocketErrored	SocketErrorEventArgs	Voice WebSocket exception path

Subscribe and Unsubscribe

using DisCatSharp.EventArgs;
using DisCatSharp.Voice;
using DisCatSharp.Voice.EventArgs;

public static void WireVoiceEvents(VoiceConnection connection)
{
    connection.UserSpeaking += OnUserSpeaking;
    connection.UserJoined += OnUserJoined;
    connection.UserLeft += OnUserLeft;
    connection.VoiceReceived += OnVoiceReceived;
    connection.VoicePacketDropped += OnVoicePacketDropped;
    connection.DaveStateChanged += OnDaveStateChanged;
    connection.DaveOpcodeObserved += OnDaveOpcodeObserved;
    connection.VoiceSocketErrored += OnVoiceSocketErrored;
}

public static void UnwireVoiceEvents(VoiceConnection connection)
{
    connection.UserSpeaking -= OnUserSpeaking;
    connection.UserJoined -= OnUserJoined;
    connection.UserLeft -= OnUserLeft;
    connection.VoiceReceived -= OnVoiceReceived;
    connection.VoicePacketDropped -= OnVoicePacketDropped;
    connection.DaveStateChanged -= OnDaveStateChanged;
    connection.DaveOpcodeObserved -= OnDaveOpcodeObserved;
    connection.VoiceSocketErrored -= OnVoiceSocketErrored;
}

private static Task OnUserSpeaking(VoiceConnection _, UserSpeakingEventArgs e)
{
    Console.WriteLine($"[SPEAK] user={e.User?.Id} ssrc={e.Ssrc} flags={e.Speaking}");
    return Task.CompletedTask;
}

private static Task OnUserJoined(VoiceConnection _, VoiceUserJoinEventArgs e)
{
    Console.WriteLine($"[JOIN] user={e.User.Id} ssrc={e.Ssrc}");
    return Task.CompletedTask;
}

private static Task OnUserLeft(VoiceConnection _, VoiceUserLeaveEventArgs e)
{
    Console.WriteLine($"[LEAVE] user={e.User.Id} ssrc={e.Ssrc}");
    return Task.CompletedTask;
}

private static Task OnVoiceReceived(VoiceConnection _, VoiceReceiveEventArgs e)
{
    Console.WriteLine($"[RX] user={e.User?.Id} seq={e.Sequence} pcm={e.PcmData.Length} missing={e.MissingFrames} conceal={e.IsConcealmentFrame}");
    return Task.CompletedTask;
}

private static Task OnVoicePacketDropped(VoiceConnection _, VoicePacketDroppedEventArgs e)
{
    Console.WriteLine($"[DROP] reason={e.Reason} user={e.User?.Id} ssrc={e.Ssrc} seq={e.Sequence} detail={e.Detail}");
    return Task.CompletedTask;
}

private static Task OnDaveStateChanged(VoiceConnection _, DaveStateChangedEventArgs e)
{
    Console.WriteLine(
        $"[DAVE FSM] {e.OldState} -> {e.NewState} via {e.Handler}; " +
        $"protocol={e.ProtocolVersion}; senderEncrypted={e.IsActive}; reason={e.Reason}");
    return Task.CompletedTask;
}

private static Task OnDaveOpcodeObserved(VoiceConnection _, DaveOpcodeEventArgs e)
{
    Console.WriteLine($"[DAVE FLOW] {e.Direction} OP{e.Opcode} len={e.PayloadLength} seq={e.Sequence} binary={e.IsBinary}");
    return Task.CompletedTask;
}

private static Task OnVoiceSocketErrored(VoiceConnection _, SocketErrorEventArgs e)
{
    Console.WriteLine($"[VOICE WS ERROR] {e.Exception.Message}");
    return Task.CompletedTask;
}

DAVE Readiness

DaveStateChangedEventArgs.NewState describes the control plane. DaveStateChangedEventArgs.IsActive describes whether the currently executing sender transform is encrypting. They intentionally differ during transitions:

• An established sender can report ReadyForTransition or Downgrading with IsActive == true while it keeps using the old epoch.
• After OP22 executes a protocol-0 downgrade, the event reports Inactive with IsActive == false, but protocol-0 media remains usable.
• ProtocolVersion is the currently executing sender version. A merely prepared next version does not replace it.

Use the connection readiness properties when deciding whether media can flow:

if (!connection.IsE2eeUsableForSend)
    Console.WriteLine("Outbound media is currently gated by the configured pending-audio policy.");

if (!connection.IsE2eeUsableForReceive)
    Console.WriteLine("Inbound media cannot currently be processed.");

Use an explicit wait when the application requires an encrypting DAVE sender:

bool daveReady = await connection.WaitForDaveActiveAsync(TimeSpan.FromSeconds(5));
if (!daveReady)
{
    // This can still be usable protocol-0 passthrough. Inspect the readiness
    // properties and apply the application's encryption policy.
}

DaveOpcodeObserved reports both server-to-client and client-to-server traffic. In the corrected transition sequence, OP23 is observed after successful receiver preparation and before OP22; OP22 has no acknowledgement. Invalid OP29 or OP30 processing produces client-to-server OP31 with the same transition ID, followed by a fresh OP26.

Related configuration:

• VoiceConfiguration.MaxDaveProtocolVersion
• VoiceConfiguration.DavePendingAudioBehavior
• VoiceConfiguration.EnableDebugLogging
• VoiceConnection.EnableDebugLogging

Runtime Logging Control

If you only want deep diagnostics for one problematic call, toggle logging on that connection instead of globally:

connection.EnableDebugLogging = true;
// reproduce issue, inspect logs
connection.EnableDebugLogging = false;