Troubleshooting & FAQ
Common issues and fixes, the gotchas worth knowing, and answers to frequent questions.
Gotchas worth knowing
Edits and uploads go to the device's current bank, which is RAM — they're lost on power-off or bank-switch. To keep them: do a WRITE on the device, or restore to a user bank from the editor. Back up your bank (Utility → BACKUP) before bulk operations, and never disconnect mid-transfer. More in RAM vs saved.
- One USB owner at a time — close other MIDI applications (and Korg's editor) while the bridge is running; only one program can hold the device.
- Pattern playback needs
GLOBAL → MIDI CLK = AUTOon the device. - Remote sampling & record give no feedback in the editor — watch the device screen.
- Panel edits only transmit while the device is on its sample-edit page; press RECEIVE (or refocus the window) to re-sync after fiddling with the hardware.
Troubleshooting
| Symptom | Fix |
|---|---|
| "microSAMPLER not responding" / "no inquiry reply" | The app shows a panel with a Retry button: power-cycle the device (off, then on) and click Retry — no need to restart the bridge. The bridge also retries (incl. a USB reset) on its own first. |
| "BRIDGE OFFLINE" | The local bridge isn't running — start it with the launcher (or
sudo python3 native-tools/bridge.py); the page reconnects by itself. |
| macOS won't open the launcher ("unidentified developer") | It's unsigned — approve it once: right-click (Control-click) → Open → Open. On newer macOS without that option, double-click once, then System Settings → Privacy & Security → Open Anyway. See Getting started for the Terminal alternative. |
| Device not found / permission error | Run with administrator rights (the launcher does this), check the cable, and close any other MIDI app holding the device. On Windows, switch the driver to WinUSB with Zadig. |
| Edits made on the device don't show in the app | The microSAMPLER only transmits panel edits while it's on its sample-edit page. Press RECEIVE (or just refocus the window) to re-read the bank. |
| Pattern play does nothing | Set GLOBAL → MIDI CLK = AUTO (or EXT MIDI) on the device. |
| A connected MIDI keyboard doesn't play | Tick MIDI IN on the Samples view and approve the browser's Web MIDI prompt. Web MIDI needs Chrome, Edge or Firefox (not Safari). |
| Uploaded sample sounds wrong | The device plays 16-bit audio at fixed rates; the editor resamples automatically — re-upload if you changed the source file. |
| USB seems stuck after many reconnects | Power-cycle the microSAMPLER — heavy connect/disconnect churn can wedge its USB firmware, which only a power-cycle fully resets. |
FAQ
Is this made or supported by Korg?
No. It's an independent, unofficial project, not affiliated with or endorsed by Korg, and it contains no Korg software or firmware. The protocol was reverse-engineered for interoperability with hardware you own.
Why does it need administrator rights (sudo)?
Your operating system's MIDI driver normally owns the device's USB interface. The bridge needs elevated rights to take it over while it runs; it releases the device when it exits.
Do my edits save automatically?
No — edits go to the current bank, which is RAM. WRITE to a user bank on the device, or restore a backup into a user bank from the Utility view, to keep them across power cycles. Back up before bulk changes.
Can I use it without a microSAMPLER?
Yes. Library mode opens bank backups (Korg .msmpl_bank files
or this app's ZIPs) and extracts their samples as WAVs and patterns as MIDI, with no hardware. There's also
a --mock mode for exploring the interface.
Can I run it alongside my DAW?
Not at the same time — the device can only have one USB owner, and its sample/pattern transfers aren't ordinary MIDI. Close the DAW (and any other MIDI software) while the bridge is running, and close the bridge before using the microSAMPLER as a USB-MIDI device in your DAW.
Will it work on Windows?
It's experimental and untested there. libusb can't open the device until its USB driver is switched to WinUSB with Zadig — see Getting started.
Is my data safe?
The software is provided "as is", without warranty. It writes to the device's memory, so back up your banks before bulk operations and never disconnect mid-transfer. The author accepts no responsibility for any damage to your device or loss of data.
Didn't find it? Open an issue or check the changelog on GitHub.