A KVM switch brings a cost-effective and convenient way to manage our daily work and entertainment. It allows us to switch between multiple PCs using just one set of keyboard, mouse, and one (or more) monitor. It simplifies the management of multiple hosts, improves work efficiency, and saves space and costs.

However, when using a KVM switch, you may encounter some common issues. We will now introduce some of these problems and provide solutions to help you make better use of a KVM switch.

Problem 1: The KVM switch is not working properly.
Solution: First, check if the switch’s power indicator light is on and ensure the power source is properly connected. If there’s a power switch, make sure it’s in the “On” position. Check all the connection cables to ensure they are correctly connected and they are working well. If the problem persists, try to reboot the KVM switch.

Problem 2: The KVM switch’s lights are not on and it won’t power on.
Solution: Check if the power cable is well connected. Try replacing the power adapter to determine if the issue is due to a faulty power adapter or a problem with the KVM switch itself.

Problem 3: The KVM switch is on but nothing shows on the display or it shows “no signal”.
Solution: First, check if the input source is powered on, and ensure that you have switched to the corresponding channel where the input source is connected.

If this is done right and the problem still persists, try connecting the host and monitor directly to see if the cable you are using is functioning properly. If there is still no display, it might be a cable issue. Try it with a high-quality cable.

If the connection works, the cables and devices are all good. You shall try setting a lower resolution output (such as 720p or 1080p) and then reconnecting to the KVM switch to test if the monitor displays an image. If it works with the adjusted resolution, it might be an issue with resolution compatibility. Check the KVM switch’s specifications and adjust your resolution output.

If the direct connection works but there’s still no image when connected to the KVM switch, it may be a compatibility issue. Try using different input sources and display devices for testing.

If you’re using a KVM switch from AV Access, please feel free to turn to our support at [email protected]. Send us an email with your test results, a simple diagram of your setup, the KVM switch model and S/N number, the input source type and model (including the graphics card), and the monitor’s model. Our support team is here to help.

Problem 4: Certain displays do not show when using a KVM switch for your multi-screen setup.
Solution: First, check if all the cables are properly connected; additionally, on the one monitor that is displaying, you can check whether other monitors are identified by the source device.

Here’s how to check: Go to the system settings on the PC -> Display (in Windows 10/11, right-click and select “Display Settings”). If the non-displaying monitor is recognized, it should appear as follows:

This check will help determine if the issue lies with the input source recognition for the non-displaying monitor.

If the monitor is identified by the source device and the light is on even though there is no image, you shall try the solution in Problem 3; if you are using any adapters, converter cables, or docking stations in your setup, consider trying a different adapter/docking for testing.

Note: most DisplayPort to HDMI cables on the market only support one-way transmission, which means the signal can only be transmitted from the DP end to the HDMI end. It won’t work backward.

Problem 5: The output resolution is not right using the KVM switch.
Solution: This may be because of a mismatch in EDID between the input device and the display device. To resolve this problem, try powering off and then restarting the KVM switch when everything is connected in the setup.

If rebooting the devices doesn’t help, please double-check the KVM switch’s specifications and make sure it’s compatible with the input source resolution and the resolutions supported by the output display. If it is not compatible, consider sending back the KVM switch and getting a new one that matches your setup.

Problem 6: The screen flickers with the KVM switch connected.
Solution: This issue may be because of the unstable connection between the KVM switch and the monitor. Check your cables to see if there is any faulty one, and make sure they are not loose and are all well plugged into the port. If you’re using any adapters, converter cables, or docking stations in the setup, it’s possible that some are incompatible with the KVM switch. You may try replacing the adapter, converter, or docking station with a reputable brand to see if the flickering issue is resolved.

Problem 7: The display works fine, but the USB peripherals are not functioning.
Solution: First, check whether the KVM switch and the host device are properly connected via the USB cables provided by the manufacturer. Basically, a KVM switch groups connecting ports by hosts. Don’t mess up the connection between different host machines. If the USB host cables are well connected and the problem still persists, try switching to a new USB port on your PC/laptop, or try using new USB devices to see if it’s a USB device compatibility issue.

Source: https://www.avaccess.com/blogs/guides/common-problems-with-kvm-switch-1/