Duplicate Audio Playback (echo) on HLS Streams with ArtPlayer

[nt74]

Bug: Duplicate Audio Playback (echo) on HLS Streams with ArtPlayer

Describe the bug

When playing an HLS stream (for example, Alpha TV) on Arch Linux, IPTVnator produces duplicated audio — a clear echo effect.
After pressing Pause, the video stops, but the audio keeps playing in the background.
This indicates that multiple WebKit/GStreamer media pipelines are active simultaneously.

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Environment

• OS: Arch Linux
• Audio system: PipeWire / PulseAudio
• App binary: /usr/bin/IPTVnator (ELF 64-bit, not stripped)
• Default video player: ArtPlayer
• Backend: WebKitGTK + GStreamer
• Tested stream:

[https://alphalive-i.akamaihd.net/hls/live/682132/AlphaTV/playlist.m3u8](https://alphalive-i.akamaihd.net/hls/live/682132/AlphaTV/playlist.m3u8)

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Steps to Reproduce

1. Launch IPTVnator.
2. Add and start the Alpha TV HLS stream:

[https://alphalive-i.akamaihd.net/hls/live/682132/AlphaTV/playlist.m3u8](https://alphalive-i.akamaihd.net/hls/live/682132/AlphaTV/playlist.m3u8)

3. Observe normal playback (audio + video).
4. Press Pause — the video stops, but audio continues playing.
5. Check active audio sinks:

pactl list sink-inputs | grep -E 'application.name|media.name|pid'

Example output:

application.name = "IPTVnator"
media.name = "Playback Stream"
application.name = "IPTVnator"
media.name = "Playback Stream"

→ Confirms two concurrent audio streams active at the same time.

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Debug Evidence

GStreamer Debug Log (GST_DEBUG=3,webkit*:5):

Full logs gst.log available if requested and needed that shows multiple internal MSE-based players created by WebKit:

<MSE-media-player-0>
<MSE-media-player-1>
<MSE-media-player-2>
<MSE-media-player-3>

Each player transitions into the PLAYING state but is not destroyed when playback is paused or replaced.
As a result, multiple GStreamer audio pipelines remain active, producing duplicated audio output.

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Likely root cause

IPTVnator uses ArtPlayer as its default player, which internally relies on WebKitGTK + GStreamer for playback.
When new playback starts (or when pausing a stream), previous MediaPlayerPrivateGStreamer instances are not properly destroyed, leading to:

• Multiple parallel GStreamer pipelines, and
• Audio continuing to play from hidden WebKit instances even after pause.

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Expected Behavior

• Only one active media pipeline (audio/video) should exist at any given time.
• When playback is paused, both audio and video should stop.
• When starting a new stream, previous pipelines should be fully destroyed.

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Suggested Fix

Before initializing new playback in ArtPlayer, ensure the previous instance is fully cleaned up:

video.pause();
video.removeAttribute('src');
video.srcObject = null;
if (hls) { hls.destroy(); hls = null; }
if (mediaSource) { try { mediaSource.endOfStream(); } catch(e){} mediaSource = null; }

Make sure that:

• Existing ArtPlayer or WebKit media instances are cleanly destroyed before new playback begins.
• The Pause button triggers a full pipeline stop within GStreamer, not just a UI pause on the <video> element.

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Additional Data

• Verified on Arch Linux using Alpha TV HLS stream.
• pactl list sink-inputs confirms duplicate active playback streams.
• Full GStreamer debug log (gst.log) is available on request if needed for reference.
• No strace logs were used — only gst.log for diagnostics.

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[nt74]

gst.log