Phone Island: WebRTC/Janus stability issues after network changes and standby

[edospadoni]

Description

Phone Island experiences several stability issues related to Janus/WebRTC connections after network changes, standby/lock screen return, and rapid WiFi toggling.

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Issues

1. React Error #310 - App crash on quick WiFi toggle

Scenario: Rapidly disconnecting and reconnecting WiFi causes the application to crash with React error #310 (too many re-renders / infinite loop).

Cause: The socket ping check interval continues running during reconnection, and stale ping timeouts set the socket_down alert even after the socket has already reconnected, triggering repeated reload cycles.

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2. Error 469 "Unexpected ANSWER" after network changes

Scenario: After network changes (WiFi switch, VPN toggle) or returning from system standby, incoming calls fail with Janus error 469.

Cause: The jsepGlobal (SDP offer) becomes stale after network changes. When the client tries to answer with an outdated offer, Janus rejects it.

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3. Multiple Janus sessions being created

Scenario: After network disruption, multiple Janus sessions are created in rapid succession, causing resource leaks and unexpected behavior.

Cause: The destroy call was targeting the wrong reference (janus.current instead of the actual session instance), and there was no guard against concurrent initialization attempts.

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4. Session destroyed but no new one created

Scenario: After certain network events, the Janus session is destroyed but a new one is never created, leaving the WebRTC in a broken state.

Cause: Session cleanup was performed before checking if initialization was already in progress, causing a race condition.

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5. Infinite reload loop when network is down

Scenario: When the network goes completely offline, the app enters an infinite reload loop trying to reconnect.

Cause: The alert-based reload mechanism had no cooldown and no check for actual network availability.

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6. Audio warm-up destroys active calls (NethLink)

Scenario: In NethLink, returning from lock screen with an active call causes the call to be terminated.

Cause: The phone-island-init-audio event triggers a test call for audio warm-up without checking if there's already an active call in progress.

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Affected Components

• phone-island - WebRTC.tsx, Socket.tsx, App.tsx
• nethlink - PhoneIslandPage.tsx, ipcEvents.ts, main.ts (for NethLink-specific issues)

[tonyco97]

Testing release: https://github.com/nethesis/ns8-nethvoice/releases/tag/1.5.4-testing.11

NethLink testing release: NethServer/nethlink#80 (comment)