Streamed audio that stays clean, in sync and in surround

How Punktfunk carries game sound, surround and your microphone, keeps audio in step with the picture, and what to check when it crackles.

The picture is fine, but the sound crackles, lags or arrives in stereo.

What the stream carries

• Opus at 48 kHz in 5 ms packets, or uncompressed stereo with Lossless under Audio format.
• Stereo, 5.1 or 7.1 under Audio channels. Linux and Windows hosts both send real surround.
• Your microphone, if you turn it on, with echo cancellation.

In sync

At connect, client and host measure the offset between their clocks. The client lines each sound up with its picture in small crossfaded steps, so drift never builds into lag. When the bitrate leaves room, each audio packet also carries the one before it, so a single loss costs nothing; a longer gap is filled in instead of clicking.

When it still crackles

• Linux host, only audio stutters: another device clocks the host's output, usually a loopback. Remove it.
• Windows host, sound worse than at the desk: the captured device mixes below 48 kHz or in fewer channels. Raise it in the sound settings.
• Audio behind the picture: reconnect once; use a cable or 5 GHz Wi-Fi.

Full steps: Audio troubleshooting and Why do I hear myself.