WebRTC to HLS Audio/Video sync out issue

[yashtandon113]

Short description

As observed when their are packet losses during the publishing of the WebRTC stream, the A/V goes out of sync in HLS playback but is not able to recover even after the network issue resolves. Their is no issue with the WebRTC playback.

The playback needs to be started again in order to make it in sync.

Environment

• Ant Media Server version: v2.13.0

Steps to reproduce

1. Publish the WebRTC stream

2. Start the HLS playback. The stream plays fine if their is no network issue for the publisher and player.

3. Create the packet losses manually using the Network Link Conditioner

4. Check the logs and see if below logs start generating

67345:2025-02-11 20:21:54,377 [vert.x-worker-thread-25] INFO i.a.e.adaptive.WebRTCEncoderAdaptor - Video time (281657) and audio time (282200) are misaligned by 543ms, exceeding the allowed margin of 500ms. This may indicate a network issue. Aligning times now. Stream ID: stream1.

5. Check the HLS playback again (Their will be A/V sync out.)

6. Turn off the Network Link Conditioner and check the HLS payback

Expected behavior

The A/V sync out should recover if their are no more packet losses

Actual behavior

The A/V sync out does not recover on HLS playback even if the network issue resolves. Their was no A/V sync issue observed in WebRTC playback.