6. Troubleshooting¶

6.1 USB Connection Issues¶

Issue: The Rhino exhibits intermittent connection problems, instability, or appears to disconnect and reconnect frequently. This typically manifests as effects stuttering, dropping out momentarily, or the device appearing offline in VPforce Configurator.

Common Causes & Solutions:

Check the following items in order:

1. USB Hub

   • If you are currently using a USB hub, disconnect it and connect the Rhino directly to your PC
   • USB hubs can introduce latency, power delivery issues, and signal integrity problems
   • Test the direct connection for stability

2. USB Port

   • Try a different USB port on your PC
   • Some USB ports have better power delivery or less electrical noise than others
   • Test multiple ports to identify if the issue is port-specific
   • If available, try USB 3.0/3.1 ports (blue ports) rather than USB 2.0 (black ports)

3. USB Cable

   • Try a different USB cable if possible
   • USB cables can degrade over time or have internal damage
   • A faulty cable is a common cause of intermittent connection issues

4. DC Power Plug

   • Inspect the DC power connector on the back of the Rhino
   • If the DC power plug pulls out easily or feels loose, vibrations during operation might be causing intermittent power connection loss
   • Poor DC connections can also introduce ground loops, causing electrical noise and instability
   • Ensure the power plug is firmly seated and making good contact
   • This is a frequent cause of instability during intense FFB effects

6.1.1 USB Isolator Recommendation¶

As a best practice or if you continue to experience intermittent connection issues after testing the above steps, or if your PC has noisy USB power delivery, consider using a USB isolator. A USB isolator is a device that sits between your PC and the Rhino, providing electrical isolation that eliminates ground loop noise and reduces EMI (electromagnetic interference) that can cause connection instability.

Benefits of a USB isolator:

• Eliminates electrical noise from your PC’s USB bus
• Provides cleaner power delivery to the Rhino
• Can resolve connection issues in systems with high electrical noise (common in gaming rigs with multiple high-power devices)

This is a proven solution for users experiencing persistent USB stability issues, particularly in systems with many power-hungry components.

Where to Find USB Isolators:

Search for AduM3160 isolator boards on AliExpress, Amazon, or other electronics retailers. The AduM3160 is a popular, affordable USB 2.0 isolator IC commonly available on ready-made isolator boards. When searching, look for:

• “AduM3160 isolator board” or “USB isolator AduM3160”
• Pre-assembled USB isolator modules (no soldering required)
• Boards with both USB-A connectors or USB-A to USB-C options

Cost is typically low (under $10-20 USD), making it an economical troubleshooting step if you suspect USB noise issues.

6.2 WinUSB / WebUSB Firmware Update Issues¶

Issue: On Windows 10/11 with firmware 1.0.16 and older, the Rhino may appear correctly in Windows, but WinUSB fails to operate, preventing firmware updates through WebUSB. Users may see network errors in the WebUSB tool. This problem is fixed in newer firmwares.

You can apply a simple registry fix to restore WebUSB functionality. This requires administrative privileges.

Steps:

• Press Start, type PowerShell, right-click Windows PowerShell, and select Run as administrator.
• Paste the following command and press Enter: HKLM:\\SYSTEM\\CurrentControlSet\\Enum\\USB\\VID_FFFF&PID_2055&MI_03\\\*\\DeviceParameters\" -Name \"DeviceInterfaceGUID\" -Value
• Unplug the Rhino from the USB port and plug it back in.
• Test the connection in the WebUSB tool - firmware updates should now work as expected.

6.3 Motor faults¶

6.3.1 FAULT_UNSTABLE¶

Issue: The Rhino reports a FAULT_UNSTABLE error. This fault typically occurs suddenly, often preceded by an audible thump or impact sensation from the device.

Note: The device’s fault message usually identifies which motor (or axis) triggered the fault. Check the indicated motor/axis first — it typically points straight to the side that needs inspection.

Cause: This fault is most commonly caused by belt slippage on either the X-axis or Y-axis. When the belt connecting a motor to its pulley loses tension or alignment, the motor and pulley can slip relative to each other. The sudden slip causes the controller to detect an unexpected position change that doesn’t match the expected motor command, triggering the stability check and generating the fault. The audible thump is often the moment when slippage occurs.

Resolution:

1. Check belt tension: Inspect the axis belt which produced the fault. The belts should be firm but not over-tightened.

2. Re-tighten if necessary: If either belt is loose, carefully tighten it to restore proper tension. See the Belt Tensioning Guide for detailed instructions.

3. Run Auto Calibration: After adjusting tension and alignment, launch the VPforce FFB Configurator and run Auto Calibration from the Settings tab.

4. Verify calibration values: Once calibration completes, check the calibration values. You should see values around C:~2000 for both axes. If the values are significantly different, the belts may need further adjustment.

6.3.2 FAULT_UNDERVOLTAGE¶

Issue: The Rhino reports a FAULT_UNDERVOLTAGE error, indicating that the supply voltage has dropped below 8 volts.

Cause: This fault occurs when the controller detects insufficient voltage to operate safely. The threshold is set at 8V to protect the motor drivers and ensure reliable operation.

If the undervoltage fault occurs under load (during active force feedback or high-torque movements), it typically indicates one of the following:

• Poor electrical connection: Loose or corroded power connector, inadequate wire gauge, or high resistance in the power path
• Failing power supply: PSU unable to maintain voltage under current draw, particularly during peak demand
• Insufficient PSU capacity: Power supply rated below recommended specifications for the motor configuration

If the fault occurs at idle (no force feedback active), it may indicate:

• PSU output voltage set too low: Check that the power supply is configured for the correct output voltage (typically 24V or 48V depending on motor configuration)
• Faulty PSU: Power supply unable to maintain stable output even without load

Resolution:

1. Check power connections: Inspect all power cables and connectors between the PSU and the Rhino controller. Ensure connections are tight, clean, and free of corrosion.

2. Verify PSU voltage output: Use a multimeter to measure the PSU output voltage under no load. It should match the rated voltage for your motor configuration (typically 24V or 48V).

3. Test under load: If possible, monitor the PSU voltage while operating the Rhino under typical load conditions. Significant voltage sag (drop) indicates insufficient PSU capacity or poor connections.

4. Upgrade wire gauge: If using long cable runs or thin wires, consider upgrading to heavier gauge wire to reduce voltage drop.

5. Replace or upgrade PSU: If the power supply cannot maintain adequate voltage under load, replace it with a higher-capacity unit meeting the recommended specifications for your motor configuration.

6.4 - Game Specific Troubleshooting¶

Various items can cause issues with FFB depending on the sim in question. This section will cover common issues and basic troubleshooting steps that can be used to identify and fix the problem. This section is a living list that will be updated as new issues/causes/solutions are identified.

6.4.1 - DCS¶

By default, the Spring effect, which is the primary ‘FFB’ effect type, is owned and managed by DCS. The TelemFFB application does not alter the spring effect unless one of the several override options are enabled.

If FFB is not working, follow the below procedure:

6.4.1.1 Ensure FFB is enabled in the DCS Misc. settings¶

1. Even with FFB disabled, DCS will create a disabled FFB effect (which renders the joystick limp). However, it will never ‘start’ the effect, so it remains limp even after loading into an aircraft.

   

2. Ensure the ‘FF Tune’ settings for the axes are non zero and at the value you intend (default is %100 and recommended to keep it at %100)

   1. This involves going into a modules’ axis settings, ensuring ‘Foldable View’ is disabled, selecting the axis binding and then choosing the ‘FF Tune’ button at the bottom.

   

   2. This is the ‘strength’ of the spring effect that DCS will use for that axis for that aircraft. Recommended to leave it at %100

6.4.1.2 Test without TelemFFB running¶

1. If the issue persists, TelemFFB is not at fault. Proceed to next step

2. If the issue goes away, likely some configuration inside TelemFFB is causing it.

   1. Check the ‘Active Effects’ panel on the TelemFFB Monitor page. Look for any spring override type effects and disable any which are active.

   

   2. If the cause is one of the effects, please read the documentation for the effect and ensure you understand its use and purpose. All of the TelemFFB override type effects have very specific use cases.

   3. If no active effects are causing the issue, check to see if you are pushing a VPforce Configurator profile or are using the Configurator Gains override feature.

      

      • Both of these options could make it seem like FFB is not working. If you are setting the master gain or spring gain to 0 with configurator overrides, or you are pushing a configurator profile with ‘sticky spring’ or the spring gain slider turned down, it will seem as if “FFB is not working”

   4. If TelemFFB has been determined to be the cause, but the above steps did not reveal the issue, reach out to the #TelemFFB-User channel on the VPforce discord

6.4.1.3 Check your configurator settings¶

1. Make sure that your master-gain and spring gain sliders are nonzero and are high enough that you feel the spring force you are expecting. These sliders define the maximum force that the Rhino can generate and if they are low/zero, it does not matter what the game sets the spring effect at, it will be no stronger than the combination of those sliders.

2. Make sure you do not have ‘Sticky’ enabled in the spring effect on the VPforce configurator ‘Effects’ tab.

   • This option tells the Rhino to ignore the spring effect from the game and use the one that is configured there in the Effects tab.

     

3. If the issue is with in-game trimming, ensure you do not have ‘Override Trim’ enabled in the hardware force trim section of the VPforce Configurator Effects tab

   • This option tells the Rhino to ignore the spring center information from the game and control the spring center using the hardware trim bindings in the Effects tab

   

4. Check your potentiometer settings.

   • Make sure the Pot#1 (and 2, if applicable) are configured as you intend and that the current values are what you expect. If your Pot is configured for Master Gain or Spring Gain and turned all the way down, FFB will seem to not work.

6.4.1.4 Check for 3rd party app issues¶

1. vJoy

   1. vJoy is known to cause issues with FFB, particularly ef the FFB options are enabled, which they typically are by default when vJoy is installed.

      

   2. SimHaptics by rKApps

      • SimHaptics has an ‘Auto Start’ feature that is known to break FFB for DCS. The app tries to start at the same time the aircraft in DCS is loading and this somehow interferes with DCS starting the FFB Spring effect.

2. The Nuclear Test

   If all of the above fails to reveal the issue, try with a fresh Saved Games folder. This will remove any active mods, or any 3rd party app that makes use of the DCS export environment as a potential cause of the issue

   1. Close DCS and rename your ‘DCS’ (or whatever is active) saved games folder to something like ‘DCS.backup’

   2. Start DCS. It will create a completely clean ‘DCS’ folder with no mods, export scripts or even bindings.

   • Here you can choose to copy your bindings from the config/input folder in your real DCS.backup folder over to the new test folder. Restart DCS after doing so

If the issue still persists, then you either did not complete all of the steps above, or there is something unknown occurring. As you will have already determined TelemFFB not to be the issue, reach out to the #Support channel on the VPforce Discord.