Some (or all) of the USB ports one of my DisplayPort KVMs don’t work. I swear they worked before, but after trying the USB2 ports on the back, I also stopped using the other USB2 and 3 ports since their performance was inconsistent.
I have two of these same KVMs and need the USB bandwidth of two KVMs because I have cameras, mics, speakers, displays, and many other devices.
For the same device, if I plug it into the other KVM, it works on the same ports. The model I have is the 2-PC 3-DisplayPort 10Gb USB model.
Is there a reason that’s the case? Can I fix it or reset it somehow?
After some extensive testing with USB Device Tree Viewer, I have more information.
The USB3 ports are working, but the USB2 ports are not. I thought maybe the port on my computer or the cable was bad, so I swapped both, and there’s no change.
I tried plugging in my USB3 device through a USB2 extension and into both USB3 ports. Those work fine. Plugged into USB2 ports with or without the extension doesn’t yield any connection.
I tried all the USB2 ports and got no connection to my Windows PC or a Mac laptop. I’m not going through any hubs either. It’s a direct connection to my PC.
USB2 devices do receive power from those ports. Hopefully, that helps narrow down what might be the issue.
Summary
- USB2 ports don’t work.
- USB2 ports give devices power.
- USB3 ports work.
- USB2 devices on USB3 ports work.
Unplug the KVm for a minute solid all power and USB cables. See if that resets it.
If not you’ll probably have to email me so I can diagnose further. Maybe a power surge on the data lines messed up the internal USB2/3 bridge on the data side? But usually it’s just you need to long power cycle the KVm because the internal protection circuit is kicking in
I think you’re right about a power surge.
I plugged in two Aputure battery-powered lights into the USB slots and all of a sudden the red light turned off, and I heard the sound of a relay switching on and off over and over again.
It looks like these devices draw a ton of power over USB-C when plugged into a USB port. I was thinking I could charge them over the KVM since it’s powered. Guess not! 
I tried plugging both into a CalDigit Element Hub and only 1 charges at a time, so they definitely pull a lot of power.
After unplugging them from the KVM, my mouse receiver now works over USB2 on the front port. Because of all the wires, it’s extremely difficult to test the back ports, but one of them worked too. I’m going to assume they all work now because those HID ports appear to be connected.
When I say USB2 ports, am I wrong? Are these are USB1 ports and that’s why they’re labeled HID and Console?
Right now, plugging in a device that only supports as low as High Speed doesn’t work.
Example:
wSpeedsSupported : 0x0C (High-Speed, SuperSpeed)
bFunctionalitySupport : 0x02 (lowest speed with all the functionality is ‘High-Speed’)
Hmm… On the other KVM, the USB2 port shows this:
Port maximum Speed : High-Speed (Companion Port 1-8-4-2-2-2 supports SuperSpeed)
After powering everything down, unplugging USB cables (not DisplayPort), and waiting 5-10 min, only my mouse’s wireless receiver works.
No other device I’ve tried has worked in the USB2 port, but they work in the USB3 port:
- Samsung Galaxy phone.
- 2xDisplayLink adapter.
- NVMe drive reader.
The hid ports are meant for hid devices not general usage. They sniff the hid protocol. Hid covers more than just keyboards and mice and can include media devices / universal video codec / universal audio codec.
The power brick for the KVm is only 1.5 amps…that’s the total amount of power draw it would support via USB. Not much. If you need a lot i suggest using an Anker brand powered USB hub. Glad it’s working again.
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