KVM Model:
Serial on box: MKAG-8KT3114
Name on box: “4 Ports HDMI 2.1 KVM Switch with 10Gbps USB3.2, Serial Control, HDCP / EDID Management, Audio Embed / Extract”
Name on product page: “HDMI 2.1 KVM w/EDID & Serial Control - Single Monitor - Four Computer”
USB Interface (5-gigabit or 10-gigbit):
Box says 10Gbps
Problem:
Hi! I just got ahold of an L1 “HDMI 2.1 KVM w/EDID & Serial Control - Single Monitor - Four Computer”. I ordered this as an upgrade to my previous solution of an HDMI switch and physically moving a USB hub with mouse and keyboard between machines, to manage the three machines I keep at this desk. It’s mostly working, and at least working better than my previous setup. Unfortunately, I’m experiencing some problems using the USB HID ports. This is preventing me from using the KVM keyboard commands, so that I can only switch the active device by pressing the buttons on the KVM itself, which is fine but less convenient.
I have connected three machines via HDMI cable and USB-C to USB-A adapter for slots 1, 2, and 3. Here’s the hardware in question:
Keyboard: SteelSeries Apex RAW
Mouse: Logitech M500 USB wired Laser Scroll Mouse M-U0007
Machine #1: Gaming and personal PC running Windows 10 LTSC.
Machine #2: Home server PC, running Ubuntu 20.04.01 LTS.
Machine #3: Work laptop, running Fedora 40 (KDE Spin).
Initially, I tried connecting the mouse and keyboard to the two USB HID ports on the back of the KVM, next to the power connector, one on top of the other. When I first did this, the mouse and keyboard both worked on #1. The keyboard worked on #2 and #3, but not the mouse. The KVM keyboard commands were working as expected.
From here I tried moving the mouse and keyboard USB connections around to troubleshoot. I found that the mouse and keyboard are consistently recognized by all three connected machines when, instead of using the USB HID ports, I connect them to the non-HID ports, e.g. the USB port on the back of the KVM on the opposite side as the USB HID ports, and the non-HID USB port on the front of the KVM.
Given this, I thought I would connect the mouse to a non-HID port and the keyboard to a USB HID port. But after these troubleshooting steps, I can no longer get any of the connected devices to recognize the keyboard when it is connected via a USB HID port. (This includes the USB HID port on the front of the KVM.) The KVM keyboard commands also are no longer recognized, not even when the keyboard is connected via a USB HID port.
Thoughout all of this, the keyboard was receiving power when connected to any given USB port, given that the backlight was on even when inputs were not recognized.
I tried power cycling the KVM as another troubleshooting step, after seeing a post where this apparently fixed a similar issue for someone else. Doing so caused some funny business with the screen resolution with the Win10 machine, which was solved by disconnecting and reconnecting its respective HDMI cable. But it did not have any apparent effect on the keyboard USB HID issue.
https forum level1techs com /t/usb-hid-ports-not-working-l1t-dp-1-4-dual-kvm/168438 (Sorry for the malformed link. I seem to not have permission to post links.)
Here are photos of the front and back of the KVM, with the mouse and keyboard currently connected to non-HID ports:
Can I please get some guidance on troubleshooting steps to hopefully fix this HID issue?