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The Level1Techs KVM (Keyboard, Video Mouse) Switch - 4k/60hz monitor & USB Switchbox | Level One Techs


#141

If you post it here, I can confirm if it’s the same or a similar issue I’m having.


#142

Brief background on my issue.

I was using the dual-kvm with a single monitor. The screen would occasionally go black for a second and come back on. I recently took everything apart and put it back together (computer and cabling). Was experimenting with 2 monitors. The computer would black out as before but would not come back until reboot (via SSH). Went back to single monitor and no improvement over 2 monitors (so worse than before somehow).

Brief system spec: Supermicro X11SSL-F, Xeon E3-1230 v6, Radeon WX5100, LG 43UD79-B, Solus (up to date)

The issue has not yet happened on my Macbook Air, but I use it sparingly and it can take hours for the issue to appear.

It’s definitely running along the monitor’s power cable. I can see if it’s hitting anything else in the cable management when I get home… It is on a sit/stand desk, so it is probably running by the motor…

Here is sudo journalctl -b via SSH after the display loses the signal. Nothing stands out to me, but this sort of issue is not within my area of expertise. Is there a utility I can use to monitor the status of the DP handshake/signal status?

Apr 05 01:41:52 REDACTED budgie-wm.desktop[1192]: Window manager warning: Buggy client sent a _NET_ACTIVE_WINDOW message with a timestamp of 0 for 0x2200008 (Authentica)
Apr 05 01:41:54 REDACTED psensor.desktop[1338]: [2018-04-05T05:41:54] [ERR] lmsensor: Cannot get value of subfeature fan1_input: Can't read.
Apr 05 01:41:56 REDACTED psensor.desktop[1338]: [2018-04-05T05:41:56] [ERR] lmsensor: Cannot get value of subfeature fan1_input: Can't read.
Apr 05 01:41:57 REDACTED polkitd[845]: Operator of unix-session:c2 successfully authenticated as unix-user:REDACTED to gain ONE-SHOT authorization for action org.gsmartcontrol for unix-process:14714:9830799 [bash /usr/bin/gsmartcontrol-root] (owned by unix-user:REDACTED)
Apr 05 01:41:57 REDACTED pkexec[14718]: pam_unix(polkit-1:session): session opened for user root by (uid=1000)
Apr 05 01:41:57 REDACTED pkexec[14718]: pam_systemd(polkit-1:session): Cannot create session: Already running in a session
Apr 05 01:41:57 REDACTED pkexec[14718]: REDACTED: Executing command [USER=root] [TTY=unknown] [CWD=/home/REDACTED] [COMMAND=/usr/sbin/gsmartcontrol]
Apr 05 01:41:58 REDACTED org.a11y.Bus[14731]: Activating service name='org.a11y.atspi.Registry'
Apr 05 01:41:58 REDACTED org.a11y.Bus[14731]: Successfully activated service 'org.a11y.atspi.Registry'
Apr 05 01:41:58 REDACTED org.a11y.atspi.Registry[14745]: SpiRegistry daemon is running with well-known name - org.a11y.atspi.Registry
Apr 05 01:41:58 REDACTED psensor.desktop[1338]: [2018-04-05T05:41:58] [ERR] lmsensor: Cannot get value of subfeature fan1_input: Can't read.
Apr 05 01:41:58 REDACTED budgie-panel.desktop[1206]: <warn>  [hz] Warning: exit: Command line did not parse.
Apr 05 01:41:58 REDACTED budgie-panel.desktop[1206]: <warn>  [app] execute_smartctl(): Smartctl binary did not execute cleanly.
Apr 05 01:41:58 REDACTED budgie-panel.desktop[1206]: <warn>  [app] StorageDevice::execute_device_smartctl(): Smartctl binary did not execute cleanly.
Apr 05 01:41:58 REDACTED budgie-panel.desktop[1206]: <warn>  [app] SmartctlParser::parse_section_info_property(): Unknown property "Temperature Warning"
Apr 05 01:41:58 REDACTED budgie-panel.desktop[1206]: <warn>  [app] SmartctlParser::parse_section_data(): Unknown Data subsection encountered.
Apr 05 01:41:58 REDACTED budgie-panel.desktop[1206]: <warn>  [hz] FS warning: Error while opening file "/proc/scsi/sg/devices": No such file or directory.
Apr 05 01:41:58 REDACTED budgie-panel.desktop[1206]: <warn>  [app] {anonymous}::read_proc_scsi_sg_devices_file(): Sg devices file doesn't exist.
Apr 05 01:42:00 REDACTED psensor.desktop[1338]: [2018-04-05T05:42:00] [ERR] lmsensor: Cannot get value of subfeature fan1_input: Can't read.
Apr 05 01:42:02 REDACTED psensor.desktop[1338]: [2018-04-05T05:42:02] [ERR] lmsensor: Cannot get value of subfeature fan1_input: Can't read.
Apr 05 01:42:04 REDACTED psensor.desktop[1338]: [2018-04-05T05:42:04] [ERR] lmsensor: Cannot get value of subfeature fan1_input: Can't read.
Apr 05 01:42:04 REDACTED budgie-panel[1206]: IconTasklistApplet.vala:418: Invalid application! hexchat.desktop
Apr 05 01:42:04 REDACTED budgie-panel[1206]: IconTasklistApplet.vala:418: Invalid application! vlc.desktop
Apr 05 01:42:06 REDACTED psensor.desktop[1338]: [2018-04-05T05:42:06] [ERR] lmsensor: Cannot get value of subfeature fan1_input: Can't read.
Apr 05 01:42:08 REDACTED psensor.desktop[1338]: [2018-04-05T05:42:08] [ERR] lmsensor: Cannot get value of subfeature fan1_input: Can't read.
Apr 05 01:42:09 REDACTED audit[12303]: SECCOMP auid=4294967295 uid=1000 gid=1000 ses=4294967295 pid=12303 comm="chrome" exe="/opt/google/chrome/chrome" sig=0 arch=c000003e syscall=273 compat=0 ip=0x7f9fe3c4c609 code=0x50000
Apr 05 01:42:10 REDACTED psensor.desktop[1338]: [2018-04-05T05:42:10] [ERR] lmsensor: Cannot get value of subfeature fan1_input: Can't read.
Apr 05 01:42:12 REDACTED psensor.desktop[1338]: [2018-04-05T05:42:12] [ERR] lmsensor: Cannot get value of subfeature fan1_input: Can't read.
Apr 05 01:42:14 REDACTED psensor.desktop[1338]: [2018-04-05T05:42:14] [ERR] lmsensor: Cannot get value of subfeature fan1_input: Can't read.
Apr 05 01:42:16 REDACTED psensor.desktop[1338]: [2018-04-05T05:42:16] [ERR] lmsensor: Cannot get value of subfeature fan1_input: Can't read.
Apr 05 01:43:06 REDACTED kernel: [drm] HBR2x4 pass VS=3, PE=0
Apr 05 01:43:06 REDACTED kernel: usb 1-12.4: USB disconnect, device number 8
Apr 05 01:43:06 REDACTED upowerd[939]: unhandled action 'unbind' on /sys/devices/pci0000:00/0000:00:14.0/usb1/1-12/1-12.4/1-12.4:1.0
Apr 05 01:43:06 REDACTED upowerd[939]: unhandled action 'unbind' on /sys/devices/pci0000:00/0000:00:14.0/usb1/1-12/1-12.4
Apr 05 01:43:06 REDACTED kernel: usb 2-1.4: USB disconnect, device number 3
Apr 05 01:43:06 REDACTED upowerd[939]: unhandled action 'unbind' on /sys/devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1.4/2-1.4:1.0
Apr 05 01:43:06 REDACTED upowerd[939]: unhandled action 'unbind' on /sys/devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1.4
Apr 05 01:43:07 REDACTED audit[12480]: SECCOMP auid=4294967295 uid=1000 gid=1000 ses=4294967295 pid=12480 comm="chrome" exe="/opt/google/chrome/chrome" sig=0 arch=c000003e syscall=273 compat=0 ip=0x7f9fe3c4c609 code=0x50000
Apr 05 01:43:07 REDACTED audit[12480]: SECCOMP auid=4294967295 uid=1000 gid=1000 ses=4294967295 pid=12480 comm="chrome" exe="/opt/google/chrome/chrome" sig=0 arch=c000003e syscall=273 compat=0 ip=0x7f9fe3c4c609 code=0x50000
Apr 05 01:43:41 REDACTED kernel: usb 2-1.4: new SuperSpeed USB device number 4 using xhci_hcd
Apr 05 01:43:41 REDACTED kernel: usb 2-1.4: New USB device found, idVendor=2109, idProduct=8110
Apr 05 01:43:41 REDACTED kernel: usb 2-1.4: New USB device strings: Mfr=1, Product=2, SerialNumber=0
Apr 05 01:43:41 REDACTED kernel: usb 2-1.4: Product: USB3.0 Hub             
Apr 05 01:43:41 REDACTED kernel: usb 2-1.4: Manufacturer: VIA Labs, Inc.         
Apr 05 01:43:41 REDACTED kernel: hub 2-1.4:1.0: USB hub found
Apr 05 01:43:41 REDACTED kernel: hub 2-1.4:1.0: 4 ports detected
Apr 05 01:43:41 REDACTED upowerd[939]: unhandled action 'bind' on /sys/devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1.4/2-1.4:1.0
Apr 05 01:43:41 REDACTED upowerd[939]: unhandled action 'bind' on /sys/devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1.4
Apr 05 01:43:41 REDACTED kernel: usb 1-12.4: new high-speed USB device number 15 using xhci_hcd
Apr 05 01:43:41 REDACTED kernel: usb 1-12.4: New USB device found, idVendor=2109, idProduct=2811
Apr 05 01:43:41 REDACTED kernel: usb 1-12.4: New USB device strings: Mfr=1, Product=2, SerialNumber=0
Apr 05 01:43:41 REDACTED kernel: usb 1-12.4: Product: USB2.0 Hub             
Apr 05 01:43:41 REDACTED kernel: usb 1-12.4: Manufacturer: VIA Labs, Inc.         
Apr 05 01:43:41 REDACTED kernel: hub 1-12.4:1.0: USB hub found
Apr 05 01:43:41 REDACTED kernel: hub 1-12.4:1.0: 4 ports detected
Apr 05 01:43:41 REDACTED upowerd[939]: unhandled action 'bind' on /sys/devices/pci0000:00/0000:00:14.0/usb1/1-12/1-12.4/1-12.4:1.0
Apr 05 01:43:41 REDACTED upowerd[939]: unhandled action 'bind' on /sys/devices/pci0000:00/0000:00:14.0/usb1/1-12/1-12.4
Apr 05 01:43:42 REDACTED audit[12303]: SECCOMP auid=4294967295 uid=1000 gid=1000 ses=4294967295 pid=12303 comm="chrome" exe="/opt/google/chrome/chrome" sig=0 arch=c000003e syscall=273 compat=0 ip=0x7f9fe3c4c609 code=0x50000
Apr 05 01:43:55 REDACTED kernel: usb 1-12.4: USB disconnect, device number 15
Apr 05 01:43:55 REDACTED upowerd[939]: unhandled action 'unbind' on /sys/devices/pci0000:00/0000:00:14.0/usb1/1-12/1-12.4/1-12.4:1.0
Apr 05 01:43:55 REDACTED upowerd[939]: unhandled action 'unbind' on /sys/devices/pci0000:00/0000:00:14.0/usb1/1-12/1-12.4
Apr 05 01:43:55 REDACTED kernel: usb 2-1.4: USB disconnect, device number 4
Apr 05 01:43:55 REDACTED upowerd[939]: unhandled action 'unbind' on /sys/devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1.4/2-1.4:1.0
Apr 05 01:43:55 REDACTED upowerd[939]: unhandled action 'unbind' on /sys/devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1.4
Apr 05 01:46:23 REDACTED audit[12303]: SECCOMP auid=4294967295 uid=1000 gid=1000 ses=4294967295 pid=12303 comm="chrome" exe="/opt/google/chrome/chrome" sig=0 arch=c000003e syscall=273 compat=0 ip=0x7f9fe3c4c609 code=0x50000
Apr 05 01:46:47 REDACTED audit[1802]: SECCOMP auid=4294967295 uid=1000 gid=1000 ses=4294967295 pid=1802 comm="chrome" exe="/opt/google/chrome/chrome" sig=0 arch=c000003e syscall=273 compat=0 ip=0x7f9fe3c4c609 code=0x50000
Apr 05 01:47:07 REDACTED audit[12303]: SECCOMP auid=4294967295 uid=1000 gid=1000 ses=4294967295 pid=12303 comm="chrome" exe="/opt/google/chrome/chrome" sig=0 arch=c000003e syscall=273 compat=0 ip=0x7f9fe3c4c609 code=0x50000
Apr 05 01:49:00 REDACTED audit[12480]: SECCOMP auid=4294967295 uid=1000 gid=1000 ses=4294967295 pid=12480 comm="chrome" exe="/opt/google/chrome/chrome" sig=0 arch=c000003e syscall=273 compat=0 ip=0x7f9fe3c4c609 code=0x50000
Apr 05 01:49:15 REDACTED audit[12303]: SECCOMP auid=4294967295 uid=1000 gid=1000 ses=4294967295 pid=12303 comm="chrome" exe="/opt/google/chrome/chrome" sig=0 arch=c000003e syscall=273 compat=0 ip=0x7f9fe3c4c609 code=0x50000
Apr 05 01:50:00 REDACTED audit[12480]: SECCOMP auid=4294967295 uid=1000 gid=1000 ses=4294967295 pid=12480 comm="chrome" exe="/opt/google/chrome/chrome" sig=0 arch=c000003e syscall=273 compat=0 ip=0x7f9fe3c4c609 code=0x50000
Apr 05 01:50:50 REDACTED audit[12303]: SECCOMP auid=4294967295 uid=1000 gid=1000 ses=4294967295 pid=12303 comm="chrome" exe="/opt/google/chrome/chrome" sig=0 arch=c000003e syscall=273 compat=0 ip=0x7f9fe3c4c609 code=0x50000
Apr 05 01:53:07 REDACTED audit[12480]: SECCOMP auid=4294967295 uid=1000 gid=1000 ses=4294967295 pid=12480 comm="chrome" exe="/opt/google/chrome/chrome" sig=0 arch=c000003e syscall=273 compat=0 ip=0x7f9fe3c4c609 code=0x50000
Apr 05 01:53:07 REDACTED audit[12480]: SECCOMP auid=4294967295 uid=1000 gid=1000 ses=4294967295 pid=12480 comm="chrome" exe="/opt/google/chrome/chrome" sig=0 arch=c000003e syscall=273 compat=0 ip=0x7f9fe3c4c609 code=0x50000
Apr 05 01:55:35 REDACTED audit[12303]: SECCOMP auid=4294967295 uid=1000 gid=1000 ses=4294967295 pid=12303 comm="chrome" exe="/opt/google/chrome/chrome" sig=0 arch=c000003e syscall=273 compat=0 ip=0x7f9fe3c4c609 code=0x50000
Apr 05 01:56:09 REDACTED audit[1802]: SECCOMP auid=4294967295 uid=1000 gid=1000 ses=4294967295 pid=1802 comm="chrome" exe="/opt/google/chrome/chrome" sig=0 arch=c000003e syscall=273 compat=0 ip=0x7f9fe3c4c609 code=0x50000
Apr 05 01:57:03 REDACTED audit[12303]: SECCOMP auid=4294967295 uid=1000 gid=1000 ses=4294967295 pid=12303 comm="chrome" exe="/opt/google/chrome/chrome" sig=0 arch=c000003e syscall=273 compat=0 ip=0x7f9fe3c4c609 code=0x50000
Apr 05 02:00:11 REDACTED audit[12303]: SECCOMP auid=4294967295 uid=1000 gid=1000 ses=4294967295 pid=12303 comm="chrome" exe="/opt/google/chrome/chrome" sig=0 arch=c000003e syscall=273 compat=0 ip=0x7f9fe3c4c609 code=0x50000
Apr 05 02:00:56 REDACTED audit[12303]: SECCOMP auid=4294967295 uid=1000 gid=1000 ses=4294967295 pid=12303 comm="chrome" exe="/opt/google/chrome/chrome" sig=0 arch=c000003e syscall=273 compat=0 ip=0x7f9fe3c4c609 code=0x50000
Apr 05 02:03:07 REDACTED audit[12480]: SECCOMP auid=4294967295 uid=1000 gid=1000 ses=4294967295 pid=12480 comm="chrome" exe="/opt/google/chrome/chrome" sig=0 arch=c000003e syscall=273 compat=0 ip=0x7f9fe3c4c609 code=0x50000
Apr 05 02:03:07 REDACTED audit[12480]: SECCOMP auid=4294967295 uid=1000 gid=1000 ses=4294967295 pid=12480 comm="chrome" exe="/opt/google/chrome/chrome" sig=0 arch=c000003e syscall=273 compat=0 ip=0x7f9fe3c4c609 code=0x50000
Apr 05 02:03:07 REDACTED audit[12480]: SECCOMP auid=4294967295 uid=1000 gid=1000 ses=4294967295 pid=12480 comm="chrome" exe="/opt/google/chrome/chrome" sig=0 arch=c000003e syscall=273 compat=0 ip=0x7f9fe3c4c609 code=0x50000
Apr 05 02:03:07 REDACTED audit[12480]: SECCOMP auid=4294967295 uid=1000 gid=1000 ses=4294967295 pid=12480 comm="chrome" exe="/opt/google/chrome/chrome" sig=0 arch=c000003e syscall=273 compat=0 ip=0x7f9fe3c4c609 code=0x50000
Apr 05 02:03:07 REDACTED audit[12517]: SECCOMP auid=4294967295 uid=1000 gid=1000 ses=4294967295 pid=12517 comm="chrome" exe="/opt/google/chrome/chrome" sig=0 arch=c000003e syscall=273 compat=0 ip=0x7f9fe3c4c609 code=0x50000
Apr 05 02:03:07 REDACTED audit[12480]: SECCOMP auid=4294967295 uid=1000 gid=1000 ses=4294967295 pid=12480 comm="chrome" exe="/opt/google/chrome/chrome" sig=0 arch=c000003e syscall=273 compat=0 ip=0x7f9fe3c4c609 code=0x50000
Apr 05 02:03:07 REDACTED audit[12480]: SECCOMP auid=4294967295 uid=1000 gid=1000 ses=4294967295 pid=12480 comm="chrome" exe="/opt/google/chrome/chrome" sig=0 arch=c000003e syscall=273 compat=0 ip=0x7f9fe3c4c609 code=0x50000
Apr 05 02:03:07 REDACTED audit[12480]: SECCOMP auid=4294967295 uid=1000 gid=1000 ses=4294967295 pid=12480 comm="chrome" exe="/opt/google/chrome/chrome" sig=0 arch=c000003e syscall=273 compat=0 ip=0x7f9fe3c4c609 code=0x50000
Apr 05 02:04:06 REDACTED audit[12303]: SECCOMP auid=4294967295 uid=1000 gid=1000 ses=4294967295 pid=12303 comm="chrome" exe="/opt/google/chrome/chrome" sig=0 arch=c000003e syscall=273 compat=0 ip=0x7f9fe3c4c609 code=0x50000
Apr 05 02:04:36 REDACTED audit[12303]: SECCOMP auid=4294967295 uid=1000 gid=1000 ses=4294967295 pid=12303 comm="chrome" exe="/opt/google/chrome/chrome" sig=0 arch=c000003e syscall=273 compat=0 ip=0x7f9fe3c4c609 code=0x50000
Apr 05 02:04:50 REDACTED audit[1802]: SECCOMP auid=4294967295 uid=1000 gid=1000 ses=4294967295 pid=1802 comm="chrome" exe="/opt/google/chrome/chrome" sig=0 arch=c000003e syscall=273 compat=0 ip=0x7f9fe3c4c609 code=0x50000

#143

By the motor. I’d definitely check that.

The monitor’s power cable is probably not an issue in itself though. I don’t think it would be creating enough of a field to induce interference.


#144

Yeah, I’m going to just run the DP cables loose and see if that fixes the problem. If it does, I’ll try to cable manage them in a separate area under the desk.

I’m using overkill gauge power cables… not sure if that makes a difference either way…


#145

I’m not sure it would. It definitely helps, but the most important factor is current and insulation, not AWG.


#146

Yeah, I just wonder to what extent the insulation is stepped up between gauges…


#147

I couldn’t say.


#148

I made an interesting discovery with this KVM today. My monitor, an LG 38UC99, frameskips at 75 Hz if no AMD GPU is connected. When I tried connecting my Surface Book (which has Nvidia/Intel graphics) to the monitor, it would frameskip at 75 Hz. However, I noticed that if I switch to the SB through the KVM after powering on my main desktop which has an AMD GPU, then the SB runs fine at 75 Hz.

If I reboot the SB, the “fix” doesn’t persist, goes back to frameskipping at 75 Hz. But toggling back and forth from my main desktop to the SB, gets it working again.

Just found this interesting. I wasn’t expecting the 75 Hz to work, but nice that it does.


#149

Any updates on this? It seems like the pre-order might not happen or that there are delays, but is there an expected availability?


#150

I think Wendell’s prioritizing the bug fixing at the moment. There are some show-stopping problems with it on AMD and/or Linux.


#151

Probably up for order (no preorder should be necessary, next batch already ordered) around May 28 or so +/-

Still investigating some issues sgtawesomeauce and others ordered. going to see if its a signal conditioning issue though, sent some stuff to people to test.

also one weird bug with a usb headset… trying to reproduce that


#152

would you like a tester? I’ve always been direct-attaching my headset, but I can try running it through the KVM.


#153

++, thank you for the update.


#154

FWIW update on my end, I took everything apart and put it back together again. Seems to be working fine now, so DP cable interference was likely to blame. Kind of nuts that it took a complete shutdown to restore the display when I was having the issue before.

I do still get occasional black screen but it comes back within a couple seconds. Here is the dmesg immediately afterwards.

[17906.495429] [drm] {3840x2160, [email protected]}
[17906.526337] [drm] HBR2x4 pass VS=3, PE=0
[17954.887141] [drm] {3840x2160, [email protected]}
[17954.917559] [drm] HBR2x4 pass VS=3, PE=0
[22136.566338] show_signal_msg: 25 callbacks suppressed
[22136.566340] solus-sc[9424]: segfault at 35 ip 00007fdc0f596a20 sp 00007ffe47582490 error 4 in libglib-2.0.so.0.5400.3[7fdc0f54f000+112000]
[28155.537142] [drm] Status: 
(END)

I think it’s just a DRM AMDGPU bug. I know there are numerous fixes incoming on Linux kernel (currently on 4.15.17-65.current).


4k Displayport Cable Blackout
#155

the nouveau driver is especially a turd in not retrying like you’re supposed to. just fwiw


#156

AMD in my case but yes, it definitely required a power cycle to renegotiate the connection.


#157

Is there a full list of hotkeys somewhere? Other than what’s in the manual. I’d like to switch to scroll lock as it’s interfering with games. I would like a full list for any other things I might be interested in


#158

Is there any way to get notified when the new batch is available? There is going to be a new run for the Dual monitor variant, right?


#159

Yes and yes. I will reply on this thread so subscrive/notify on it

We are about 2-3 weeks away +/-


#160

I absolutely NEED one of the dual-monitor versions. Can anyone confirm if this supports HDCP 2.2 pass thru?