For years, the Nvidia Shield has served as the standard for high-end media playback on a Plex server due to its support for lossless audio formats like Dolby Atmos, TrueHD, and DTS:X, alongside partial support for the Dolby Vision HDR standard.
While the Apple TV offers capable hardware, it has historically lacked the same level of native format support. But a new, free, open-source alternative Plex player called Rivulet aims to close that gap by bringing both lossless audio and Dolby Vision Profile 7 Full Enhancement Layer (FEL) support to the platform.
Check it out in my latest video!
Before looking at how the software operates, I want to note that this coverage is part of my monthly paid sponsorship with Plex. As with all of my Plex sponsorships, the company did not review or approve this content prior to publication, and all observations are my own. Get yourself a Plex Pass here!
Rivulet connects directly to an existing Plex server via the official API, pulling in libraries, watchlists, and the Discover section automatically. Playback progress and bookmarks sync back to the server, allowing users to transition between Rivulet and the official Plex client on other devices without losing their place. Although the application is relatively new, the interface is responsive and includes standard navigation features like intro and credit skipping, chapter selection, subtitle management, and the option to force server-side transcoding instead of direct play. It also provides a real-time technical readout showing active decoding metrics, alongside an insights tab that displays cast information and content notes.
The primary technical distinction of Rivulet is how it handles Dolby Vision Profile 7 FEL, the dual-layer format typically found on 4K Blu-ray discs. Because the Apple TV lacks dedicated hardware to decode this enhancement layer, Rivulet uses the device’s CPU to pre-process the FEL data before sending it through the Apple TV video pipeline. This software-based approach requires substantial processing power. On my third-generation Apple TV 4K, the app played FEL content without stuttering, though second-generation hardware may encounter performance limits. When the processor cannot keep up with the FEL data stream, the app automatically falls back to single-layer Dolby Vision Profile 8 to preserve smooth video playback and lossless audio.
Lossless audio formats are handled through a similar CPU-driven process. While standard audio tracks are passed directly to tvOS, formats like Dolby Atmos and TrueHD are decoded on the Apple TV processor into lossless multichannel audio before being routed to the speakers. Users with height speaker configurations—such as my 5.1.2 setup—can configure height channels within the app’s playback settings. However, due to current CPU constraints on the third-generation Apple TV, Rivulet cannot process Dolby Vision FEL and Atmos height channels simultaneously. Users must choose between the full video enhancement layer or overhead audio channels when playing Profile 7 media, though non-FEL files support height channels without issue.
Beyond local media libraries, the app integrates with Plex’s Live TV and DVR functionality for over-the-air antennas. Users can watch live broadcasts, schedule recordings, and utilize a multi-view mode to display up to four live television feeds at once, provided their tuner hardware has Enough available channels. The live tuner integration currently supports ATSC 1.0 broadcasts, as ATSC 3.0 is not supported at this time.
Rivulet is available now as a free download on the tvOS App Store, with its source code publicly accessible under a non-commercial license. With a newer Apple TV model featuring an upgraded processor on the way, I plan to test whether the additional headroom allows the software to handle both full enhancement layer video and overhead audio channels at the same time. Limitations aside, Rivulet offers Apple TV owners a practical method to unlock fuller audio and video fidelity from their existing Plex libraries.