HID issues with KVM 1.4, webcam/microphone/keyboard/DAC

Hi all,

Recently purchased a KVM 1.4 dual monitor dual pc switch, very happy with how the monitors are working however I’m having some difficulties getting my keyboard/microphone/DAC/webcam recognised when using the HID ports.

Using the USB Hub port all devices have been recognised and do pass data. However when connecting through a HID port I do get a nice beep from the KVM and they do receive power but no device is recognised. The one exception to this being my wireless mouse which does correctly work via the HID ports.

The Peripherals I’m using:
Mouse: Logitech G Pro X superlight
Keyboard: Mechwild mercutio 40% (flashed with QMK)
Webcam: Logitech C920 HD Pro webcam
DAC: Schiit Modius

Currently only have 1 Windows 10 PC hooked up to the KVM switch as I’m waiting on a new macbook from work.

AFAIK I’ve got the most up to date firmware for all peripherals so kind of stumped where to go from here, ATM relying on a USB splitter and connecting all devices through 1 USB hub port. Normally I would attribute the lack of support due to how niche most of the peripherals are, but I find it odd one Logitech device works while another does not.

Any help would be greatly appreciated.


The hid ports are meant for hid devices. Mouse, keyboard, touch screen, macroboard, etc.

If you want to use lots of non hid devices I’d recommend a powered usb3 hub.

Avc/uvc Audio video devices probably also work via hid since those are part of usbc spec, but if it needs a driver it may not work in the hid ports. For the keyboard try disabling nkey rollover of you have that.

Qmk does work for sure, I use that, however if you have an atmega328 p in software USB mode that’s not going to work because it’s outside USB spec. Works fine on stm32 based qmk and also works fine with atmega that use the hardware USB port instead of the slightly weird and broken “soft USB” hack.

My mistake, thought mic/webcam were also HID for some reason. I’ll look into a powered USB hub.

Thanks Wendell,

they can be, if they follow the avc/uvc standard and don’t do anything weird.

Just curious, what did you end up using to solve this? I have a switch on the way and will be running a very similar setup as you.