Go-librespot PulseAudio Error: 'Did Not Receive Last Pong' & Fix

by RICHARD 65 views

go-librespot's PulseAudio Issues: Did Not Receive Last Pong

Introduction: go-librespot and PulseAudio Problems

Hey guys, let's dive into a common issue when using go-librespot, a popular Spotify Connect client, particularly when dealing with PulseAudio. The main symptom is the dreaded "did not receive last pong from dealer" error, which can lead to instability and interrupted audio playback. This problem seems to primarily affect users running go-librespot with native PulseAudio, while those who switch to ALSA (with an ALSA bridge) often find a reliable solution. Let's explore the details of this issue, the troubleshooting steps, and the underlying reasons behind it.

When you're using go-librespot with PulseAudio, you might encounter a situation where the application fails to receive a "pong" from the "dealer." What does this mean? In simple terms, go-librespot relies on a communication system, and the "pong" is a kind of "I'm still here" signal from the dealer, which is crucial for maintaining the connection. If the app doesn't receive this signal within a certain timeframe (as the error messages show, 60 or 90 seconds), it assumes that the connection is lost, causing the application to shut down and causing an error. This can be really frustrating when you're trying to enjoy your music.

Many users have found a workaround by switching to ALSA and using an ALSA bridge. ALSA, or Advanced Linux Sound Architecture, is another sound system in Linux that manages audio hardware. An ALSA bridge essentially allows go-librespot to communicate with ALSA instead of PulseAudio. This setup often works, but it might involve some extra configuration. For example, the provided information includes a script that sets up an ALSA bridge, which is used to redirect audio to it.

Understanding the Error and Its Context

The provided error logs offer valuable clues, showing the exact nature of the problem. Here are some essential details from the logs:

  • Error Messages: The log contains the crucial "ERRO[0112] did not receive last pong from dealer, 60s passed" and "ERRO[0142] did not receive last pong from dealer, 90s passed" messages. These indicate that the program is not receiving the expected "pong" signals from the dealer. These time intervals (60 and 90 seconds) are critical because they determine how long the system waits for a response before considering the connection dead.
  • Abort Signal: The "SIGABRT: abort" signal suggests that the program is abruptly terminating. This is triggered because the application detects the lack of a connection, leading to the termination of the application and the stopping of music playback.
  • Goroutine Information: The provided information also contains a goroutine stack trace. Goroutines are lightweight threads that can run concurrently. By analyzing this stack trace, developers can pinpoint where the issue arises within the application. Although it's a bit technical, it's essential for pinpointing the source of the problem.

Troubleshooting Steps and Configurations

Let's examine the suggested troubleshooting steps and configurations provided. First, the user moved from native pulse to ALSA. This approach is a common solution to the "did not receive last pong" error. Here's how to do this and what it means.

  • ALSA Bridge Setup: The user employed an ALSA bridge setup to facilitate communication between go-librespot and the audio system. This setup involved running a specific command to download and execute a script, which sets up the bridge. Using an ALSA bridge is a common solution that can bypass or mitigate certain PulseAudio-related issues.
  • Configuration Details: The original configuration had specific settings: "audio_backend: pulseaudio." This option points go-librespot to use PulseAudio. By changing the audio backend, you can potentially eliminate the issue. In the working ALSA configuration, this setting is likely changed to ALSA. Other parameters like "bitrate," "device_name," "device_type," and "log_level" set various audio and logging options. These configurations do not affect the "pong" error, but they are crucial for tailoring the audio experience.
  • Docker Build and Start Script: The Docker setup contains a build process that includes dependencies (like git, build-base, pkgconf, alsa-lib-dev, etc.), clones the go-librespot repository, downloads modules, builds the daemon, and sets up a start script. This setup shows how to create a reproducible environment to run the program.

Root Causes and Possible Solutions

Now, let's get into the possible reasons for the "did not receive last pong" error and what could be done to fix it:

  • PulseAudio Instability: It's possible that the native PulseAudio backend has some issues that lead to connection problems. PulseAudio's behavior can vary based on the system configuration, and sometimes it has communication problems.
  • Network Issues: In certain scenarios, network issues may affect the communication between go-librespot and the dealer. Even a small network issue can prevent "pong" signals from reaching their destination.
  • Resource Conflicts: In some cases, resource conflicts between PulseAudio and other apps could be the reason for the "pong" error. When multiple applications are competing for audio resources, communication could be disrupted.
  • Software Bugs: If the issue persists even with the ALSA configuration, it's possible there could be a bug inside go-librespot. Sometimes the internal timing or the way the connection is handled could be flawed.

If you encounter this issue, here's what you can do:

  • Switch to ALSA: As proven to work in many cases, using an ALSA bridge seems to be the most straightforward and effective solution.
  • Check Network Connectivity: Ensure that there are no network issues that could disrupt communication. A stable network is important.
  • Update Software: Make sure that your go-librespot and other related software are updated to the latest versions. Updates often fix existing bugs.
  • Review System Logs: Examine the PulseAudio system logs and other system logs for any error messages that could indicate the root cause of the problem.
  • Report the Issue: If the problem continues, report it to the go-librespot developers. Include your logs and configuration files to help them diagnose the issue.

Conclusion

The "did not receive last pong from dealer" error is a real challenge when using go-librespot with PulseAudio. By understanding the error messages, using ALSA, and troubleshooting systematically, you can increase the stability of your audio streaming experience. The provided insights from the original report provide helpful details for solving the problem and avoiding further problems.