Emby iOS app won’t play Music over WireGuard/cellular (Web player works)

[Neon_Eddie 0]

Has anyone seen the iOS app fail to start music playback over VPN/cellular where the web player works? Any known issues with the embedded localhost:12344 web UI mode, Direct Play FLAC, or a setting to force the app to use the same streaming method as Safari?

App never requests audio stream (no /Audio GETs), only metadata/playstate.

Setup

• Emby Server on Synology (Synology package)

• Access from iPhone over cellular using WireGuard VPN (split-tunnel; LAN 192.168.X.X/24 routed through VPN)

• Server accessed by LAN IP (e.g., http://192.168.X.XXX:8096)

• Safari web player works over cellular+WireGuard (music plays normally)

• Emby iOS app fails over cellular+WireGuard: UI loads, can browse library, but music never actually plays (timer doesn’t advance, eventually skips tracks/stops)

What happens

• In the iOS app, pressing Play starts a session in the server admin “Now Playing” screen, often showing Direct Play (FLAC), but the phone never produces audio and often stops/skips after a short time.

• On Wi-Fi it may eventually play, but on cellular via VPN it consistently fails.

• Safari on the same phone, same VPN, same URL plays immediately.

Server logs (Debug enabled)

• The iPhone makes normal API calls for metadata/artwork and playstate, e.g.:

  GET /emby/Users/.../Items/...

  GET /emby/Items/.../Images/...

  POST /emby/Sessions/Playing/Progress

  POST /emby/Sessions/Playing/Stopped

• The session often stops with Position 0 ms (never actually starts playback).

tcpdump evidence
Captured on the NAS while pressing Play in the iOS app (filtering iPhone VPN IP 10.0.0.2 to Emby port 8096):

• Observed GETs for metadata and images, and POSTs for playstate/progress.

• No requests for any audio stream endpoint were observed (no GET /Audio/..., no GET /Items/.../stream, no download/stream GET at all).

• The app connects to 8096 only (no 8920), exchanges a small amount of data, then closes the connection shortly after.

Key headers observed from the iOS app requests:

• Origin: http://localhost:12344

• Referer: http://localhost:12344/
  (which suggests the app is using an embedded local web UI/proxy)

Conclusion
Network/VPN path is proven good because Safari plays audio fine over the same cellular+WireGuard connection. The iOS app appears to never initiate the actual audio stream request, only control/metadata/playstate traffic, then stops/idle-skips.

Versions

• iOS app reports: Emby for iOS 2.2.50

• iPhone OS shown in UA: iPhone OS 18_7

• Server web dashboard version shown in logs: Emby Web 4.9.3.0 (server package on Synology)

Bottom line...The app never plays the music.