failed to read packet

[Lepterion]

Describe the bug
Calling UDPConn.ReadPacket() consistently fails when reading from a Discord voice UDP connection. The method almost never successfully reads a packet once the connection is opened.

Error
The following error is logged on every call to ReadPacket():

failed to read packet: read udp 192.168.0.108:61986->34.0.245.81:50006: wsarecv: A message sent on a datagram socket was larger than the internal message buffer or some other network limit, or the buffer used to receive a datagram into was smaller than the datagram itself.

To Reproduce

1. Create a voice connection using VoiceManager.CreateConn.
2. Open the voice connection and set the speaking flag.
3. Continuously read packets from the voice UDP connection in a goroutine using UDPConn.ReadPacket().

vs := global.Session.VoiceManager.CreateConn(guildID)

err := vs.Open(ctx, channelID, false, false)
if err != nil {
	return fmt.Errorf("failed to open voice connection: %w", err)
}

err = vs.SetSpeaking(ctx, voice.SpeakingFlagMicrophone)
if err != nil {
	return fmt.Errorf("failed to set speaking: %w", err)
}

go func() {
	for {
		_, err := vs.UDP().ReadPacket() // this fails
		if err != nil {
			slog.Error("error reading voice packet", "error", err)
			continue
		}
	}
}()

Expected behavior
UDPConn.ReadPacket() should successfully read incoming UDP voice packets once the voice connection is established.

Disgo Version:

• v0.19.0-rc.12
• go 1.25.3 windows/amd64

[topi314]

I've never seen that issue and can't reproduce it either lol
can you try https://github.com/disgoorg/disgo/tree/exp/increase-voice-receive-buffer?

[Lepterion]

I've never seencthat issue and can't reproduce it either lol can you try https://github.com/disgoorg/disgo/tree/exp/increase-voice-receive-buffer?

I tried to use my existing code and I can not reproduce this issue right now as well. I didn't introduce any changes to the code. But I noticed that the discord voice server has switched since the last time I tried to use voice. The branch you shared also seems to work as expected.

[Lepterion]

I've never seen that issue and can't reproduce it either lol can you try https://github.com/disgoorg/disgo/tree/exp/increase-voice-receive-buffer?

Hello again. Today I tried to use voice again, and the issue returned. The error is the same. The issue persists on your branch as well.

[topi314]

I am pretty clueless why this is happening. If you want to debug this further maybe we can chat in discord. The invite link is in the readme

[Lepterion]

I am pretty clueless why this is happening. If you want to debug this further maybe we can chat in discord. The invite link is in the readme

I am really interested in getting this bug fixed. I am not sure if I will be helpful enough, but I will message you on the Discord server in a couple of days.

[davfsa]

Hey!

Its possible I might have indirectly fixed this issue while working on DAVE: https://github.com/disgoorg/disgo/pull/506/changes#diff-658cf4be28f310e298f7c966d33b56e611777ba2f2d1270a845d1494aa9bdee5R302

Would you mind installing disgo from the feature/dave branch and seeing if your issue is fixed? You don't have to actually setup DAVE support, just updating might be enough :)

[Lepterion]

Hey!

Its possible I might have indirectly fixed this issue while working on DAVE: https://github.com/disgoorg/disgo/pull/506/changes#diff-658cf4be28f310e298f7c966d33b56e611777ba2f2d1270a845d1494aa9bdee5R302

Would you mind installing disgo from the feature/dave branch and seeing if your issue is fixed? You don't have to actually setup DAVE support, just updating might be enough :)

Hello. Tried that branch but unfortunately the error still occurs.

[topi314]

can you see if this is resolved in https://github.com/disgoorg/disgo/releases/tag/v0.19.0?

[Lepterion]

can you see if this is resolved in https://github.com/disgoorg/disgo/releases/tag/v0.19.0?

Hello. Sorry for a this long reply. Yes, it looks like this issue has indeed been resolved.

However, I have noticed a differrent problem. Reading packet returns "failed to decrypt frame" error whenever there is a user with camera on, even if they are silent.

Additionally, on a couple of occasions, the same error started occurring on every read after a user joined the bot when it had been alone in a voice channel for a long time (at least 4 hours).

[topi314]

probably relevant here
#5

[topi314]

@Lepterion

However, I have noticed a differrent problem. Reading packet returns "failed to decrypt frame" error whenever there is a user with camera on, even if they are silent.

I can't reproduce this
is this still a thing? if so can you show it to me or something? idk

Additionally, on a couple of occasions, the same error started occurring on every read after a user joined the bot when it had been alone in a voice channel for a long time (at least 4 hours).

a few of those errors are "normal" since its a race condition if we get the keys first, or they send audio
if it happens more than a few frames thats bad tho. Can you clarify?