Troubleshooting Guide

# Troubleshooting Guide

Real, verbatim-sourced troubleshooting content exists locally for exactly 2 SKUs (FP-8A, FP-12A) — both DSP units with a dedicated "Troubleshooting" page in their Owner's Manual. No other SKU in the 52-SKU catalog has any local troubleshooting source.

## FP-8A (FP-8A)

**Procedure:** Before powering on, carefully check whether the connection line is normal and ensure all interfaces are properly connected. If a failure occurs: (1) refer to the table below to find the reason; (2) if still unable to repair, restore the unit to its default value; (3) if still unable to repair, consult the manufacturer's customer service department.

| Malfunction | Reason & Solution |
| --- | --- |
| No Power | Is the power connection properly connected? Is the connection method correct? |
| No Sound | Has the mute operation been activated? Is the signal input channel selected correctly? |
| USB connection is not available | Is the USB cable inserted in place? Check Device Manager on the PC for a "HID-compliant device" entry — if it's not discovered, the driver/connection has failed. |

## FP-12A (FP-12A)

**Procedure:** Check all cables and connectors/terminals before powering on. General procedure: (1) refer to the table below for the reason; (2) if the amplifier is still in failure after inspection, reset it to factory preset; (3) if still failing, contact the manufacturer for after-sales service.

| Malfunction | Reason & Solution |
| --- | --- |
| No Power | Check and ensure correct power connection. Check the ACC/DC connection. |
| No Sound | Is it in mute mode? Make sure the correct input channel is selected. |
| Unable to connect USB | Check the USB connection. Check if the driver "HID-compliant device" has been installed in your PC. |

## FX-4

PENDING VERIFICATION — no dedicated Troubleshooting section in this manual. It does include an "Interference" section (noise/ground-loop guidance) — see raw ded; not reproduced here as it was not fully read/verified this session.

## All other 49 SKUs

PENDING VERIFICATION — no local manual, datasheet, or technical resource exists. Do not apply the FP-8A/FP-12A troubleshooting table to other DSP models even within the same category — hardware interfaces differ (e.g. FP-16-ULTRA has no local technical files at all per 's NO_LOCAL_TECH_FILES status).