L1KVM DP1.4 USB Problems - Firmware Update?

I have the L1KVM Dual-PC-Dual-Monitor KVM with 10G USBc inputs and I have some issues with it.

The HID ports can only be used with my keyboard and even there I have issues from time to time, most other devices, even if they are USB2 won’t work there. Mostly everything is OK, but from time to time the keyboard does not register any keys in Windows anymore. The Keyboard itself seems fine though, shortcuts for the KVM like switching inputs continue to work, but no keystroke is send to the host. If that happens I need to replug the keyboard and eventually it starts to send keystrokes to my Windows host again. But on rare occasions, I need to power cycle the whole KVM to get everything working again.

My mouse is not working correctly on the HID ports. I have the Logitech G903 Lightspeed and connect the wireless receiver to the KVM. If I plug it into one of the HID ports, the mouse works, but slows down from time to time which is super annoying. I have set the mouse to 2000DPI normally, but dragging over the desktop can suddenly reduce the DPI to 800 or lower (at least it feels that way, super laggy, more like a mouse on a rubber band or something). Plugging the receiver into one of the USB3 outs, even on a hub connected to a USB3 out works fine though.

The next thing is USB devices do not properly being handed over to my Laptop upon switching inputs. My Laptop (Dell Precision 5560 connected via a Dell Dock WD19DC) seems to recognize displays fine, but some of the USB devices don’t show up on the Laptop like my webcam (Razor Kyro) or my microphone (Shure MV7). Re-plugging those devices or power-cycling the KVM usually helps here.

Is there some newer firmware for these KVMs that I can try?

CC @wendell @EricM

No updated firmware. The usb3 ports are straight passthrough, so starting there is a good idea. Do you have the latest firmware on the dell wd19dc? The usb3 toggle on the kvm is a fairly long dis/reconnect which is “usually” enough to get devices like webcams and mics to re-recognize. Sometimes laptops respond to that situation weirdly. If you can switch from the laptop to the pc and have the webcam/mic switch (when on a usb3 port) that’s probably more the dock than the kvm.

I do have some specific firmware fixes in place for the lightspeed protocol because Of Course Everyone Wants To ReInvent The HID Protocol but I hadn’t noticed mouse weirdness. One thing is that if you load the helper software for a peripheral like a mouse or keyboard you have to start to be sure that both devices on the kvm hid ports are using the same protocol to talk to the device. on the lightspeed stuff once the driver loads how the devices talk to the pc on the wire changes. So when you switch inputs it doesn’t recover. Whereas on usb3 it is a hard reset every time and much more likely to work since it “reboots” the attached usb device.

I guess I’d start by going from laptop to windows and see if you have trouble with webcam and mic work properly. And check the dell dock firmware

Thanks, I’ll check that firmware on the Dell dock again. But I’m pretty sure it is the latest.
I also have access to another WD19DC, but this seems to be the newer model since it has no audio port (mine does have an audio apart from being identical otherwise). Maybe some chipset quirks? I’ll test that.

Regarding the HID-USB issue with the Lightspeed receiver: I have my mouse in onboard profile mode with no additional software run on the PC. Although the mouse is set to 1000Hz and my display runs at 120Hz (LG 38GN950, 3840x1600). Can that be an issue?

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