WebRTC softphone config 422 on genesyscloud_user_settings

Having some issues getting my configuration to work for WebRTC softphone settings on AU-1 BYOC. Provider 2.5.1. Apply fails with 422 on genesyscloud_user_settings.

Plan succeeds. API trace shows validation error on webrtc_enabled.

{
 "webrtc_enabled": true,
 "webrtc_quality": "high",
 "user_id": "12345"
}

Does BYOC require specific endpoint permissions? Getting Invalid refer error.