WebRTC softphone drops audio after JWT rotation on /api/v2/fetch/softphone

Voice & Telephony
1

PureCloudPlatformClientV2 throws a 401 Unauthorized on the /api/v2/fetch/softphone endpoint when the session token refreshes during an active WebRTC stream. Node version is 18.17.0 and the SDK is locked to @genesyscloud/platform-client-v2@3.12.0. The softphone widget initializes fine, but around the three minute mark the audio cuts completely. Console shows Signaling error: connection reset by peer followed by a failed PATCH /api/v2/conversations/voice/{id} call. Token rotation happens automatically via the refreshToken callback, yet the new bearer string never attaches to the WebSocket handshake. Attempts to force a re-auth with platformClient.Auth.login() fail because the STUN servers at turn.genesisys.com drop the candidate exchange immediately. The iceConnectionState flips to failed before the new token can validate. It’s doing jack all for the queue now. Architect flow routes to a standard ACD skill group, so the backend doesn’t see a disconnect until the fallback timer hits thirty seconds. Webhook logs show the participant state stays connected while the client side already shows a red phone icon. Switching to @genesyscloud/genesyscloud-webrtc didn’t help either. The underlying WebSocket client ignores the Authorization header rewrite on reconnection attempts. PureCloudPlatformClientV2 handles the initial handshake without issues, but the keep-alive pings fail once the JWT expires. Network traces confirm the TURN allocation request returns 403 Forbidden with reason: invalid credentials. App credentials in the integration dashboard are verified and the scopes include user and ucm. The softphone config JSON has useTurn: true and stunServers pointing to the default list. Nothing changes when we swap to a fresh browser profile or disable extensions. The WebSocket closes with code 1006 and the retry loop just spins.

{
 "error": "invalid_grant",
 "error_description": "Refresh token expired or revoked",
 "sdk_version": "3.12.0",
 "endpoint": "/api/v2/fetch/softphone",
 "ice_state": "failed",
 "webrtc_version": "1.2.4"
}
2

PureCloudPlatformClientV2 handles token rotation in the background, but it never patches the active /api/v2/fetch/softphone WebSocket channel. First, the SDK swaps the bearer token. Next, the signaling layer continues routing media using the old JWT. When the broker rejects it, you get that 401 and the audio bridge drops. You’ll need to intercept the refresh cycle and force a hard reset.

  • Wire up the onAccessTokenRefreshed callback to grab the fresh string
  • Call softphone.disconnect() immediately to kill the stale session
  • Reinit the widget using the updated bearer and softphone:control scope
  • Validate the handshake via a quick REST Proxy ping
platformClient.auth.onAccessTokenRefreshed((token) => {
 softphone.disconnect();
 setTimeout(() => softphone.init({ token, scopes: ['softphone:control'] }), 300);
});

The short pause clears the stale broker state. You can also hit /api/v2/fetch/softphone/softphone to verify connectivity before reattaching. Watch out for blocked event loops.