Troubleshooting

Layouts reassign all three switches at once. The FM3 boots into Presets; holding the left or right switch moves through banks.

Fractal state this directly. Use channels inside the one Amp block to get four voicings instead — that is the FM3 way.

It is one jack pair doing two jobs. Wired as a loop return, it is not an aux input.

Use Output 2's quarter-inch pair for an amp, or an XLR-to-TS cable from Output 1.

Use a Humbuster cable from Output 2. On Output 1, use the ground lift switch.

Scenes load nothing and switch seamlessly. Build song sections as scenes.

Replace duplicate blocks with channels. On an FM3 this is not an optimisation, it is the technique.

Press STORE. Changing preset with the edited indicator lit discards everything without a prompt.

Most of the time it really is a faulty or disconnected cable. Plug headphones straight into the unit: if the preset sounds fine there, the fault is downstream and nothing on the unit needs changing.

A grid can look connected and not be. Check the preset begins with an Input block and ends with an Output block, and that those correspond to the jacks you have actually cabled. Then change each block to a shunt in turn, leaving the Amp and Cab until last, and listen for where the sound returns.

If something is assigned to a volume or level control and the pedal or switch it expects is not plugged in, the level sits wherever that missing controller says — usually silence. Either remove the modifier, or set the external controller's initial value to 100% instead of 0%.

Presets you downloaded often reference a cab IR that lives on the author's unit and not yours. Point the Cab block at a factory cab and the sound comes back.

Fractal put this first for a reason — it is startling how often a brand new or long-trusted cable turns out to be the problem. Swap before you diagnose.

Check whether you are clipping the inputs or the outputs. Clipping that only appears on the loudest notes reads as a crackle rather than as distortion.

Above about 80% the unit starts running out of room and the artefacts are audible. Remove a block and see whether they stop.

Output 1 ships at −10 dBV, which is right for consumer gear and quiet into anything professional. Change it under SETUP : I/O : Audio — Output 1: Output Level — to +4 dBu.

A pedal has to be calibrated to the jack before the unit knows its travel. Until then it may read as a fixed value rather than a sweep.

Expression needs a TRS cable, not a standard guitar lead — and a volume pedal is not an expression pedal, even though it has the same socket.

Calibrating the pedal does not connect it to anything. It has to be attached to a parameter with a modifier before it does a job.

Power down, wait five seconds, then power on holding HOME until the progress bar appears. It comes up on an empty preset in location 000, which you can store over the preset that was causing it.

Power down, wait five seconds, power on holding EDIT until the progress bar appears, then SETUP > Utilities > Reset and run Reset System Parameters. This never deletes or modifies your presets.

Power down, wait five seconds, then power on holding both PAGE buttons until the emergency utility page appears, and update as normal with Fractal-Bot.

The rings say three things, not two: dim means the effect is off, bright means it is on, and fully dark means the assigned effect does not exist in the current preset. Fractal's own suggestion is to override that switch per preset with an effect the preset actually uses.

Both press-and-hold BANK functions have Upper and Lower Limits, and out of the box they cover every location. Set them to fence off the range you use — the limits count BANKS, not presets, so with three presets per bank, fifteen gigging presets is a limit of 5.

It is recoverable and nothing is broken. In almost every factory layout the middle switch's hold is Layout: Select: 9, View 1 — layout 9 being the master layout menu. Set it back in EZ Edit, or in the FC Controllers area of the editor. Resetting the factory layouts is the blunt version.

Axe-Fx III presets DO import, with caveats worth knowing: the top four rows and first twelve columns come across aligned to the FM3's grid, anything incompatible becomes a shunt, and blocks from rows 5–6 or columns 13–14 get placed wherever there is room. A converted preset can exceed what the FM3's CPU will run, in which case you get a blinking "CPU Limit - Muted" banner and no audio until you remove something. Axe-Fx II, AX8 and FX8 presets do not import at all.