Cinder

A replacement music player for the Sony NW-A55 Walkman and the rest of the NW-A50 series. It replaces Sony's music app with a faster one and keeps Sony's audio services, effects and DAC path underneath. Install it from a PC over USB; the same installer puts Sony's app back.

This is a personal project that was made for myself. If people want to tweak it and adapt it to their own use, please do, but I can't promise features or time for it. Raise issues in the issues section, but I can't promise they will be patched. Back up before you install (how), and if you have the time and skill, please contribute pull requests.

I have deliberately not included any way to sponsor or pay for this project. I want it to be free, and I don't want the obligation for support that comes with payment; as I said, I made this for me.

I am aware that using AI to create this is an unpopular decision, but I do not have the time or skill to make it in a "morally correct" way. Every feature that is added is based on whether I think it will be useful, helpful or if it is requested. This project came from me wanting something that didn't exist to the level I wanted it at the time.

I do hope in time a community will form around this project and that people will support it and use it in every way that they want to. I hope Cinder does what you want it to; if not, make a request! The best way to support it is to test, give feedback and patch.

Cinder is still in testing and development, whatever GitHub's labels say. Updates are always being pushed (at the moment at least).

What you get

• Fast. About 5.7 MB of native code, no UI framework. Sony's app is Qt.
• A real queue. Up Next with play next, drag to reorder, and playlists made on the player.
• Your library as it is. Cinder reads Sony's database, so music, playlists and liked songs stay. It also plays albums kept as one file with a .cue sheet, lists audiobooks by series, and searches artists, albums and audiobooks as well as songs.
• Short track previews. A standalone retro page previews the current queue for 4 or 15 seconds per track, using existing Sony chorus markers when available (controls and behaviour).
• USB-DAC in, LDAC out, at once. Use the Walkman as a PC sound card and send the audio on to Bluetooth headphones. Sony's app blocks this; the hardware doesn't. An optional low-latency USB DAC (about 50 ms, headphone jack only) is there for video and games, and switches off again without a restart.
• All of Sony's sound features: DSEE HX and DSEE AI, VPT, Clear Phase, DC Phase Linearizer, Vinyl Processor, Clear Bass, the 10-band EQ and tone control. Cinder drives Sony's own services rather than reimplementing them. On top: an EQ in the DAC chip itself, named presets (one per album or song if you like), your own volume curve, and a signal path that says what costs battery.
• Bluetooth codecs: LDAC as Sony ships it, plus optional AAC and SBC XQ.
• Better battery. With the screen off, Cinder powers the display hardware down and lets the chip reach its deepest idle state. Sony's audio path is untouched.
• Extras: a .scrobbler.log scrobbler, lyrics (.lrc or embedded), SensMe™ channels, FM radio with a signal meter and recording, ATRAC files, and colour palettes you drop on the drive (share and download them).
• Your layout. Open on the Library, Now Playing, the Menu or wherever you left off. Six Now Playing styles: Cinder, Nocturne, Terminal, Clock, Cassette (with your own tapes) and Winamp (with classic .wsz skins). Big view for larger text and buttons, your own font, and an optional pull-down panel for brightness, Bluetooth, night mode and the sleep timer.
• Your language. English and Simplified Chinese, chosen in the installer, and a guide for adding another.

Status

A daily player on the developer's own unit. Every CHANGELOG.md entry says whether it has run on hardware (device-verified). Per-feature state: cinder-home/STATUS.md.

Known issues

• v0.3.9 doesn't start after a fresh install (#16). Fixed in v0.3.12: install it over the top.
• Bluetooth receiver mode (Walkman as a speaker) is experimental. Playing from a Windows PC works. iPhones won't connect, and some don't list the Walkman at all.
• Experimental options, off by default: the low-latency USB DAC, FM recording, ATRAC playback and the macOS installer. Each one's state is in cinder-home/STATUS.md.
• One test unit. Other NW-A50-series models share its firmware but haven't been tried.

Supported players

Player	Already on it	Cinder	Run on the developer's A55
NW-A55	Sony stock 1.02	Supported. The main target.	Daily, now
NW-A55	Stock 1.02 + Wampy	Supported. Install over it; Wampy can stay (below).	Daily, July–September 2026
NW-A55	Walkman One 3.02	Supported. A few sound features differ (Walkman One).	Daily, September–October 2026
NW-A55	Walkman One 3.02 + Wampy	Supported. Install over it; Wampy can stay.	Late September 2026
NW-A55	Other stock or Walkman One versions	Not tried.	—
NW-A56 / A57	Any of the above	Should work. Same firmware as the A55; no reports yet.	—
A40 / A30 series, ZX300, WM1A/Z, DMP-Z1	Anything	Not supported. Use Wampy, which covers the whole MT8590 family. If you own one and can test, get in touch through GitHub.	—

A device report for a row marked "should work" or "not tried" helps, whether it works or not.

With Wampy installed

You don't need to uninstall Wampy first.

• Files: Cinder keeps its files in its own folder and leaves Wampy's alone.
• Wampy's screen: it doesn't appear while Cinder runs. Wampy draws over Sony's music app, and Cinder takes that app's place.
• Uninstalling Cinder brings Sony's app back, and Wampy works over it as before.
• Mono and soundscapes over music: the preload install option loads Cinder's library into Sony's sound service after Wampy's, and Wampy's library still loads.
• Scrobbling: Wampy's scrobbler keeps running. Cinder writes no .scrobbler.log of its own while Wampy's scrobbler is running, so no play is counted twice.

Install

1. Back up the player with wbrt (Windows). It is the proven way back for a player that no longer starts. Cinder's own cinder-rescue (on the Releases page from v0.3.21-rc1; double-click it for a page with every step on buttons) can take a second backup and put back only the partitions a boot loop broke (RECOVERY.md Step 3), but it has run on one player so far. Until it has run on more, keep a wbrt backup as well.
2. Download the installer from Releases:
   • Windows: cinder-installer-windows-x64.exe. Accept the administrator prompt; the last step needs raw drive access.
   • Linux: cinder-installer-linux-x64, run with sudo.
   • macOS (experimental): cinder-installer-macos, run with sudo. Not yet tried on a real Mac with a player; Windows or Linux is the sure route.
3. Connect the Walkman in USB mass-storage mode, run the installer, choose Install and your options. The player reboots into its updater, installs, and starts Cinder. Leave the cable in until it does.

The installer also has Update (keeps your choices) and Uninstall (restores Sony's app; music and settings are untouched). It reads the player's logs, so it reports what is really installed. The .exe is unsigned; check it against SHA256SUMS on the release.

Every option, and the developer build: install.md. Removing it: UNINSTALL.md.

If something goes wrong

Each way back to Sony's player depends on less than the one before:

• Boot with the USB cable connected → Sony's player. Needs no filesystem. (The first boot after an install ignores the cable once.)
• A file named cinderhome_off on the drive → Sony's player until you delete it. cinderhome_clear clears a latched failure and tries Cinder again.
• A build that fails to start reverts to Sony's player by itself after four boots.
• A player that doesn't start at all still has MediaTek's download mode, before any of its software: restore your wbrt backup, or put back just the broken partitions with cinder-rescue restore.

Read RECOVERY.md before you need it. Attach cinderhome.log (root of the drive) to any issue.

Walkman One

Cinder runs on Walkman One 3.02 as well as on Sony's stock 1.02, and installs the same way: Walkman One changes the key Sony's updater accepts, and the installer asks the player for its key and writes the package that key opens. Everything in Cinder works there except:

• VPT Surround, Clear Phase and DSEE AI aren't in Walkman One's sound library. Cinder shows them as unavailable rather than letting a tap do nothing.
• Clear Bass isn't in Walkman One's sound effects either. The install option Clear Bass (Walkman One 3.02 only) puts it back, in place of the DC Phase Linearizer.
• Noise cancelling (Sony's NC earphones): Walkman One never starts Sony's noise-cancelling engine, so Cinder starts it when you switch NC on. Ambient sound isn't available: Walkman One removed its filter.
• Other versions of Walkman One haven't been tried.

Coming from Walkman One:

• Sound: Walkman One's plus modes are a 3-byte change to Sony's audio library. Cinder's Sound signature install option makes the same change to your own stock files, no flashing. Its external tunings are other models' firmware and can't be reproduced. Measured at the jack, neither changes the signal (unknown321's measurements).
• Volume curve: Cinder removes Sony's regional volume limit by default; the Headphone volume curve option Sony, with region limit keeps it. Smooth (NW-WM1A) is a choice there too, if you supply Sony's table file (how).
• Reverting to stock first works; Cinder installs on stock 1.02. If it then doesn't start, you're on v0.3.9 (#16): use a newer release.

Teardown of Walkman One: analysis/RE_walkmanone_extract.md.

Contributing and building

Issues and pull requests are welcome. The most useful contribution is a device report: run one item from docs/DEVICE_CHECKLIST.md and post the result, pass or fail. Designing a palette, a screen or a whole style? Start with docs/DESIGN_GUIDE.md. CONTRIBUTING.md covers the local checks, the rules for boot-path code, and releases. Docs index: docs/README.md.

Path	Contents
cinder-home/	The C++ Home app: lifecycle, watchdogs, glue to Sony's services, the LDAC bridge, the installer payload
player/	The Rust UI (cinder-ui), its C boundary (cinder-ffi), the library reader, and host tools that render every screen to PNG
installer/	The end-user installer (Windows GUI and text UI), dependency-free Rust
rescue/	cinder-rescue: back up, verify and restore the eMMC over MediaTek's download mode
cinder-aac/	The Bluetooth AAC encoder option
analysis/, docs/	Reverse-engineering notes, audits and plans

UI work needs no device: cd player && cargo run --release -p cinder-host renders every screen to player/out/. The device build needs a matched cross toolchain; see install.md and CLAUDE.md Parts A–D.

Related projects

Wampy	Skinnable replacement UI for the whole MT8590 Walkman family. Its MAKING_OF write-ups mapped this platform first.
wbrt	Full eMMC backup and restore. Brick insurance for everything here.
Walkman One	Sony's player with region and feature locks removed.
Rockbox nwztools	.UPG packing, per-model keys and the NVP map.
scrobbler	On-device Last.fm scrobbling. If installed, Cinder's scrobbler steps aside.
Flint / Sony-sync	The developer's PC sync tools. Flint writes SensMe data and syncs likes and scrobbles.

Screenshots

All 40 screens, from Now Playing to the Windows installer: docs/SCREENSHOTS.md.

License

Cinder is free to use, change and share for any non-commercial purpose: your own player, study, hobby projects, clubs and charities. Selling it, or building it into something you sell, is not allowed. The terms are the PolyForm Noncommercial License 1.0.0. Releases up to v0.3.18 were MIT, and those copies stay MIT; contributions made before the change keep their MIT notice.

Bundled fonts are SIL OFL 1.1 (*-OFL.txt beside each). The fdk-aac encoder that the bt-aac option installs has its own licence (cinder-aac/NOTICE.fdk-aac). The repository contains no Sony code or artwork; the reverse-engineering notes describe interfaces only. Rockbox's nwztools (GPL) is used as an external tool, not vendored.

Not affiliated with or endorsed by Sony. "Walkman" and "SensMe" are Sony's marks.

As a disclaimer, a large amount of the reverse engineering work, documentation, and Rust and C++ code was written by Claude. All work was supervised and checked by a human.