(help-troubleshooting)=
Most MatchPatch problems come from one of four places:
- the wrong backend;
- missing or wrong hardware routing;
- a missing reference DI;
- a snapshot recording silence or unstable audio.
Start with the checklist below, then find the problem that matches what you see.
- Open Advanced > Diagnostics and click Run preflight check before a first hardware run or after changing device settings.
- Confirm the correct backend:
- loopback for testing without Helix;
- hardware for real Helix measurement.
- If using hardware, confirm the Helix is connected and powered on.
- Confirm the Reference DI path points to an existing WAV.
- Confirm playback and recording channels match your Helix routing.
- Confirm MIDI output and MIDI channel are correct.
- Confirm selected presets have snapshots that are not all ignored.
- If using a single
.hlx, confirm the temporary slot is filled in.
The Preflight check is the fastest way to diagnose setup problems before a full measurement. It validates the current file, selected presets, reference DI, effective settings, and hardware backend details when hardware mode is selected. For hardware mode, the native hardware check validates the selected audio device, audio channels, MIDI output, and timing settings from the Windows environment that will run the measurement.
Open Advanced > Diagnostics, then use:
- Run preflight check to validate the current setup without writing adjusted files.
- Copy diagnostic summary to copy resolved settings and recent context.
- Export diagnostic bundle to save a support bundle for a bug report.
Diagnostic bundles are designed for troubleshooting, not for moving your tone files around. They include:
- a human-readable summary;
- structured diagnostic JSON;
- effective MatchPatch settings;
- recent GUI log lines;
- recent progress events;
- hardware/preflight check results;
- retained CSV path and safe row summaries when available.
Diagnostic bundles intentionally exclude raw audio recordings, reference DI audio contents, preset or setlist contents, adjusted output files, and full retained CSV contents.
When sharing a bug report, attach the .zip created by Export diagnostic bundle
and describe what you clicked immediately before the problem. If the issue is
hardware-related, also mention whether the Helix was visible to Windows as both
an audio device and a MIDI output.
One or more preset rows or snapshot cells are red after measurement.
MatchPatch could not safely calculate a normal adjustment. It may have recorded silence, received unusable loudness data, or calculated an output level outside the Helix range.
- Open the Log tab and look for the warning.
- Check whether the snapshot recorded silence.
- Check audio routing.
- Use the recorded-output playback button if available.
- Rerun the preset after fixing routing or timing.
- If the tone really needs a special level, use manual editing or custom adjustments.
See Reading Results.
Warning: Do not keep raising output levels blindly after a failed measurement. First find out why the measurement failed.
(help-hardware-not-found)=
The GUI shows a hardware error, or measurement does not start in hardware mode.
MatchPatch cannot see the Helix audio device, MIDI output, or native hardware setup.
- Check that the Helix is powered on.
- Check the USB cable.
- Check that the Helix appears as an audio device.
- Check that the Helix appears as a MIDI output.
- In Advanced > Device, make the Audio device and MIDI output names more specific.
- If you only want to learn the app, switch Backend to
loopback.
See Hardware Measurement.
Hardware mode fails when running from WSL or a Linux-side setup.
The Windows audio/MIDI environment needed for hardware measurement is not ready.
If you are not comfortable with command-line setup, ask the person who installed MatchPatch to prepare the Windows runtime.
If you only want to continue learning the GUI, switch to loopback mode.
MatchPatch says the Reference DI WAV does not exist.
The file path in Advanced > Files points to a missing or moved WAV.
- Open Advanced > Files.
- Click Browse beside Reference DI.
- Choose an existing WAV file.
- Start again.
See Reference DI.
MatchPatch starts with different backend, routing, Reference DI, or timing settings than you expected.
The config file is not in the automatic search path, or another config file is selected in Advanced > Files.
- Open Advanced > Files.
- If the Config field points to a file, confirm it is the file you meant to use.
- If the Config field is empty, put your default config in the automatic location for your system.
Automatic config search path:
- Windows installed app:
%APPDATA%\MatchPatch\config.toml - Windows compatibility fallback:
%USERPROFILE%\.config\matchpatch\config.toml - Linux/WSL/macOS with
XDG_CONFIG_HOME:$XDG_CONFIG_HOME/matchpatch/config.toml - Linux/WSL/macOS fallback:
~/.config/matchpatch/config.toml
Measurement starts but fails with a sample-rate message.
The reference DI WAV sample rate does not match the configured audio sample rate.
- Use a reference DI recorded at the same sample rate as the Helix audio setup.
- Or change the Sample rate in Advanced > Device to match the WAV and hardware.
- Try again.
MatchPatch cannot find the audio device, or says the audio device match is ambiguous.
The Audio device field is empty, too broad, or does not match the device name.
- Open Advanced > Device.
- Make the Audio device field more specific.
- If multiple similar devices are visible, use the exact name shown by your system.
- Reconnect the Helix and restart the app if the device list changed.
Measurements are silent, wrong, or fail with bad LUFS.
The reference DI is going to the wrong playback channels, or MatchPatch is recording the wrong return channels.
- Open Advanced > Device.
- Check Recording channels.
- Check Playback channels.
- Try the normal Helix idea:
- Recording channels:
1,2; - Playback channels:
3,4.
- Recording channels:
- Use recorded-output playback to confirm signal.
See Routing And Levels.
Warning: Wrong channels can record silence and create misleading loudness numbers.
MatchPatch says there are no measurable presets or snapshots.
All selected presets are empty, all selected snapshots are ignored, or the preset selection does not match the loaded file.
- Check that presets are selected.
- Check that the ignored snapshot rule is not skipping everything.
- Check the snapshot count.
- Select a known non-empty preset.
- Try again.
See Snapshots, Solos, And Ignored Snapshots.
The GUI warns that a preset ID is required, or highlights the Preset cell.
A single .hlx preset needs one temporary Helix slot for measurement.
- Click the Preset cell.
- Enter one slot, such as
12A. - Use a slot from
01Athrough32D. - Start again.
See Normalize A Single Preset.
MatchPatch refuses to save the file.
The saved file extension does not match the input.
- Save
.hlssetlists as.hls. - Save
.hlxpresets as.hlx. - Use Save As and choose a matching filename.
Select changed or diff selection fails.
The previous file does not have the same extension as the current file.
- Open the current
.hlssetlist. - Click Select changed.
- Choose an older
.hlsversion of that same setlist.
A table edit or CSV import complains about a Helix name.
The preset or snapshot name contains a character the Helix file workflow does not allow, or the name is too long.
- Use shorter names.
- Avoid unusual symbols.
- Use letters, numbers, spaces, and common punctuation.
- For snapshot names, keep names very short.
The table shows a failed measurement, bad LUFS warning, or measurement unavailable warning.
MatchPatch did not get usable loudness data.
Common reasons:
- silence was recorded;
- wrong USB channels;
- the Helix did not switch as expected;
- the reference DI did not reach the Helix;
- the measured audio was too short for the analysis window;
- timing was too fast for effect trails.
- Check routing.
- Check the Reference DI.
- Use recorded-output playback.
- Use Default timing instead of Fast.
- Increase snapshot wait for presets with long trails.
- Rerun the affected preset.
See Measurement Timing.
MatchPatch warns that the resulting output level would be outside the Helix range.
The measurement was probably invalid, often because silence was recorded.
- Check routing first.
- Check that the preset produces sound.
- Check that the output block is active.
- Rerun the preset.
- If the preset is intentionally strange, use manual editing carefully.
MatchPatch says the Helix snapshot-assigned property limit would be exceeded.
The preset already uses close to Helix's limit of 64 snapshot-assigned properties. MatchPatch needs to assign the output block level to snapshots before it can balance snapshot loudness.
- Open the preset in HX Edit or on the Helix.
- Remove unused snapshot assignments from blocks or parameters.
- Save the preset or setlist.
- Run MatchPatch again.
Measurements vary between runs, or snapshots with delay/reverb produce strange results.
Timing is too fast. One snapshot's trails may still be ringing during the next snapshot's measurement.
- Use the Default timing preset.
- Increase snapshot wait or measurement wait.
- Run Determine optimal parameters.
See Optimize Timing.
The GUI fails to open from a WSL setup.
The graphical desktop support is not available or the required GUI packages are missing.
- If you are not technical, ask the person who installed MatchPatch to check WSLg or GUI package setup.
- If you only need hardware measurement, consider running MatchPatch from the prepared Windows environment.
(help-csv-errors)=
Loading a table CSV shows an error popup.
The CSV does not match the current table.
- Open the same setlist the CSV came from.
- Make sure the snapshot count is the same.
- Make sure preset IDs still exist in the table.
- Check that gain values are numbers.
- Check that names are short and Helix-safe.
The custom adjustment file is rejected.
The file has the wrong number of columns, a duplicate preset ID, an empty preset ID, or a non-number adjustment.
- Make one row per preset.
- Put the preset slot first, such as
01A. - Add one value column per measured snapshot.
- Leave cells empty when no custom adjustment is needed.
- Use small number values, such as
1.5or-2.
See Custom Adjustments.
After importing the adjusted file, play through the real setlist.
Listen for:
- rhythm presets that still jump out;
- leads that still disappear;
- clean sounds that feel too quiet;
- special effects that should be skipped;
- snapshot changes that feel unnatural.
If only one snapshot needs a small change, use manual editing or a custom adjustment.
Rerun measurement when:
- routing was wrong;
- the Helix was not connected correctly;
- a red row was caused by silence;
- timing was too fast;
- you changed the preset tone;
- you changed the reference DI.