53403: Server is unable to apply a remote media description

This error occurs when the Twilio Video Media Server receives a remote media description from a participant and cannot apply it. Start by checking client compatibility, because Twilio recommends using the latest Video SDK, supported browser environments, and codec settings that align with the codecs supported by the Video SFU.

• Your application is using an older Twilio Video SDK release. Twilio recommends updating to the latest JavaScript SDK release.
• If you use the JavaScript SDK, the participant is joining from an unsupported browser or unsupported WebView environment. Twilio supports recent versions of Chrome, Edge, Safari, Firefox, and Samsung Internet. iOS WebView support requires iOS 14.3 or later and JavaScript SDK 2.21.0 or later. Android WebView is not supported.
• Your application is forcing codec preferences that do not match Twilio Video codec support. In Group Rooms, the Video SFU supports VP8 and H.264 for video and Opus and PCMU for audio.
• Participants in the same Group Room negotiated codecs that are not interoperable for a later-joining client. For example, if participants are already sending VP8, a legacy Safari browser that can only receive H.264 may not be able to receive video.

• Update all clients to the latest Twilio Video SDK release before testing again.
• If you use the JavaScript SDK, verify that the participant is using a supported browser and check isSupported before connecting to the Room.
• Review any codec preferences you set in ConnectOptions. For two-participant Rooms, do not force a preferred video codec unless you need to. For Rooms with three or more participants, prefer VP8 and enable Adaptive Simulcast. Keep Opus as your audio codec unless you have a specific reason to change it.
• If you prefer H.264 on mobile clients, confirm that the device supports H.264 encode and decode before you force that codec.
• Run Twilio Video diagnostics before participants join a Room. The Video Diagnostics Application, RTC Diagnostics SDK, and Preflight API help you test device setup, connectivity with the Twilio Cloud, and media connectivity issues.

• Managing codecs
• JavaScript Platform Overview
• Insights, Troubleshooting, and Diagnostics