fix it

A double cab: the capture already contains a mic'd cabinet, and the IR Loader stacks a second speaker on top of it. . Fix: Turn the IR Loader off: turn Footswitch II past the last slot until no indicators are lit. An amp-and-cab capture has the cabinet baked in, and it cannot be separated.

The IR's high-cut is set very low, or the mic position is dark. . Fix: Move the mic position further from the center of the cone and raise the high-cut. Mic and position selection only works on the factory IRs, not on your own uploads.

No cab at all: the capture is amp-only and the IR Loader is bypassed, so you hear a raw amp with no speaker. . Fix: Turn the IR Loader on and pick a cab. Bad with the IR off: the capture probably has no cab. Bad with the IR on: it probably includes one.

Digital fizz in the top end, common to all modeling. . Fix: High-cut around 8–10 kHz on the IR, and low-cut 80–100 Hz to tighten the bottom. Also try less gain than feels right.

You're using the LEVEL knob, which is a global master, not a per-preset level. . Fix: Hold CAPTURE for two seconds to open the Capture Volume view, then use LEVEL there. Range is −24 dB to +12 dB, default 0.0. Save before moving on.

Each uploader gain-stages differently. Perceived loudness also follows spectral density, not dB, so a clean and a high-gain capture can measure the same and sound nothing alike. . Fix: Level-match by ear at playing volume, with a factory preset as your reference. The 25 factory captures are curated and consistent, and the cloud is not.

IR level differs between presets. . Fix: IR level is per-preset and doesn't affect other presets using the same IR, so it's a safe second lever.

You're using TS instrument cables on balanced TRS outputs, which costs about 6 dB and some clarity. . Fix: Use TRS cables, or TRS-to-XLR.

Only one output is connected, so panned content is missing. . Fix: Enable analog output auto-sum, added in NanOS 2.2.0, so a single cable receives a proper mono sum.

The IR's low-pass was doing level management as well as tone shaping. Removing it dumps a hotter, full-range signal downstream. . Fix: Pull the per-preset capture volume down, and add a Low-High Cut EQ in a post slot to replace the filtering the IR was doing.

Powering over USB-C while running unbalanced cables to other gear, which creates a ground loop. This is the documented number-one cause. . Fix: Power from the DC jack with a regulated supply, or switch to balanced TRS runs—ideally both.

Ground loop through the outputs. . Fix: Engage the GND ground-lift switch. Full fix for some, partial for others.

An undersized power supply. The device needs 600 mA minimum, and 500 mA supplies are below spec. . Fix: Use 9–12 V DC, 600 mA or more, center-negative, 2.1/5.5 mm. The Quad Cortex supply works. Owners confirm the Truetone 1SPOT, Boss PSB-1U and Cioks DC7.

The capture or IR itself is noisy—plenty of cloud content is. . Fix: Use the Input Gate in the Capture Volume view, and try a different capture to confirm.

Parameter Lock is on. . Fix: Hold EXIT for three seconds. This is common enough that Neural DSP put it in their FAQ.

Knob Operation Mode is set to Latching, so a knob does nothing until it passes through the stored value. . Fix: Sweep the knob through its range, or switch to immediate mode in the app's settings.

They fire on release, not on press. This is deliberate: press-and-hold reaches the tuner and tap tempo on the same two switches. . Fix: No setting changes this and there is no workaround. It is by design, not a fault, and it does hurt accuracy when starting a looper.

A bug in NanOS 2.2.0 could prevent booting when an expression or MIDI pedal is connected. NanOS 2.2.1 exists specifically to fix it. . Fix: Unplug the expression or MIDI pedal to boot, then update to 2.2.1 or later.

Power: USB-A cannot run this device, and undersized supplies cause intermittent failures. . Fix: Use 9–12 V DC at 600 mA or more, or a fully USB-C-compliant 5 V / 1.5 A source. Data works over USB-A but power does not.

Around 60 ms of silence, introduced deliberately in NanOS 2.0.0 to allow the flexible signal chain. Delay and reverb trails do continue across the change. . Fix: Keep the modulation, delay and reverb identical across all four presets—several owners report this makes it inaudible. Better still, switch effects via expression pedal or MIDI CC, which isn't a preset change and so has no gap.

This is by design. There are 64 presets but only two footswitches, giving IA/IB and IIA/IIB. The BANK button moves through capture banks, not preset banks, and it's hand-operated. . Fix: Add a MIDI foot controller over TRS MIDI Type A—presets map automatically to Program Change 0–63. Neural DSP staff have endorsed the Nektar Pacer, Morningstar MC6, Behringer FCB1010, Harley Benton MP-100 and Fortin Hydra. Otherwise, build a setlist around four combined sounds.

A confirmed bug with MIDI over the TRS port: the controller sends CCs that the cab and capture blocks mishandle. Neural DSP support has acknowledged it as a known issue with a fix planned and no date. . Fix: Drive MIDI over USB-C instead, which costs you the audio-interface use of that port. There is no other workaround.

There's a separate sanity check during the capture itself, stricter than the calibration meter. Green LEDs during calibration do not guarantee the capture will pass. . Fix: Lower the source device's output rather than the Nano's gain, and drop capture gain significantly even if the meter then reads blue. One owner needed four attempts. Solid-state gear triggers this more readily than tube amps.

BOOST engaged with GAIN already up. . Fix: Set GAIN to minimum before engaging the +26 dB BOOST. Neural DSP repeats this warning in three separate documents.

The IR Loader was engaged while capturing, baking a second cab in. . Fix: Turn the IR off before capturing, and A/B with Footswitch I as you go.

Capture level was too low, which repeatedly shows up as captures with less gain than the source. . Fix: Recalibrate for a solid green reading, and expect to take several attempts.

You're capturing a software amp sim. Multiple owners report captures of plugins missing distortion and sounding wrong, while pedal captures work fine for the same people. . Fix: No resolution has been published for this. Treat plugin capturing as unreliable on this device.

Bluetooth on this device is for pairing with the Cortex Cloud app only. There is no Bluetooth audio and no wireless headphone support. . Fix: Send audio over USB-C from a phone, tablet or laptop—iOS works well, Android is reported to crackle and isn't supported. Alternatively use an FRFR with its own Bluetooth or aux, or a small mixer.

The modeler isn't in pairing mode. . Fix: Hold EXIT and CAPTURE together for one second. The GAIN ring sweeps clockwise and the Footswitch I LED blinks slowly. Then choose Add New in the app.

On Android, the app lacks Location permission, which BLE scanning requires. . Fix: Grant Location permission to the Cortex Cloud app.

Stale Bluetooth state. . Fix: Power-cycle the pedal and restart the phone. No firmware fix has been announced.

There is no effects loop on this device. . Fix: Either capture the external preamp and load it into the capture slot, or save a preset with no capture active and run your real pedal in front, using the Nano only for cab, delay and reverb. Never route a speaker-level signal back into it.

Presets are incompatible—the Nano's fixed chain can't represent Quad Cortex routing. . Fix: Captures, however, are fully interchangeable and officially the same resolution. Since November 2025 over a thousand Quad Cortex factory captures are available to Nano owners, and NanOS 2.2.0 added a Capture V2 player. Note the Nano can play V2 captures but cannot create them.

There is no input gain control on the device, and the operating system's input level for it defaults low. . Fix: Raise the input volume in your OS sound settings for the Nano Cortex before opening your DAW. On macOS that's System Settings → Sound → Input.

Connected through a USB hub. . Fix: Connect directly to a motherboard port. Neural DSP explicitly discourages hubs.

Powered from USB and an external supply simultaneously. . Fix: Use one power source. One owner's glitching vanished when they removed the second.

Session sample rate isn't 48 kHz. . Fix: The device is fixed at 24-bit / 48 kHz. Set your session to match instead of resampling.