Surface Laptop 4 Switching results in constant USB resets

Level1 Store KVM Helpdesk
1

KVM Model:

MKAG-8KT3124

USB Interface (5-gigabit or 10-gigbit):

10 gigabit

Problem:

USB devices get stuck in a state of constantly resetting/locking up after switching away and then back to a Surface Laptop 4.

Other Notes:

I have the HDMI 2.1 4 Computer 2 Monitor KVM to switch between 3 main computers:

  • Computer 1: Windows 11 Desktop PC, ASUS B550 motherboard

  • Computer 2: Windows 10, Microsoft Surface Laptop 4 (with or without a Surface Dock 2)

  • Computer 3: Dell Optiplex Micro 7010 running Pop!_OS 22.04

  • USB 3 devices:
    Varmilo VAE88M keyboard, connected to USB 3 port due to permanent NKRO breaking hotkeys
    Roccat Kone Pro Air mouse
    Razer Basilisk X Hyperspeed mouse
    USB 3.0 Hub

  • HID Devices:
    9-key VIA-programmable keypad, for hotkey switching

Computer 1 and Computer 3 function fine for the most part, but Computer 2 (the Surface Laptop) is completely unusable after switching to another device and back to it. The issue is that the USB devices constantly reset. This manifests as:

  • the mouse cursor freezing every few seconds
  • keyboard key presses don’t register or get stuck in a repeating state
  • the Razer mouse flashes its sync light
  • if the keyboard backlight is enabled, the lights go out and back on

Windows does not make any USB disconnect/reconnect sounds when this is happening.

The Surface laptop requires a full shutdown of the laptop to get it to behave itself.

It’s a Surface Laptop 4 with the i7-1185G7 CPU. I have tried both with the Surface Dock 2, and also with the standard Surface power supply and a basic USB hub plugged into the single USB port on the Surface.

I’m limited with how much I can do on the Surface Laptop since it’s a company-provided machine. I have local admin rights to make some changes, but for the most part it’s locked down. Turning off the “allow to sleep” option for all USB hubs through Device Manager did not solve the issue, neither did disabling USB selective suspend of USB 3 hub power saving using powercfg.

2

Hmmm… thoughts @wendell ? Is it something to do with how locked down the surface is you think?

3

Another observation I made:

I had the Varmilo keyboard and Razer mouse plugged into a USB hub, then plugged into the USB 3 port on the back of the KVM. With the Surface laptop in a “misbehaving” state, I physically moved the keyboard from that USB hub, and directly into the front USB 3 port on the KVM.

At that point, the keyboard still continued to reset over and over (key lighting intermittently going on and off, and missed key presses) - exactly the same behaviour as when it was plugged into the hub.

If that original USB hub is then disconnected, the keyboard begins to work normally. Plug the hub back in, and the keyboard starts resetting again. Note that this is with the keyboard not going through the hub that I unplugged/reconnected.

And another observation - I left a USB speaker connected directly to the Surface, and switched the KVM away. I could hear regular USB disconnect chimes, which continued for several minutes, whilst the KVM is on switch to one of the other ports.

It’s almost as if Windows or some other service is getting confused about the state/hierarchy of the USB devices.