Simhub randomly causing USB disconnections

[mr-big3]

Describe the bug While simhub is open, sometimes my fan leds suddenly disconnect and turn red, green and blue, and then reconnect within 10 seconds. This happens to my case fans (Lian Li SL infinity) and CPU fan (Arctic Freezer 3 420). This also happens with my DDU, which will disconnect and reconnect within 10 seconds. Additionally, whenever this happens in iRacing, the game completely freezes for a couple seconds, and then I reconnect in the exact same spot which I disconnected at. This is not an internet issue, and I have attached an image of what the iRacing bars look like when this error happens. The disconnections seem to be limited to the fans and DDU, none of my other USB connected devices have suffered disconnects

Simhub version 9.4.11

Third party plugins All disabled

To Reproduce Steps to reproduce the behavior: I cannot reproduce it consistently, but it will always happen at some point while I have simhub open. Sometimes it happens often, and sometimes it won't happen for an entire race.

Expected behavior I hope for it not to crash, the simhub software is phenomenal and I made sure to purchase a licence, but this random disconnecting makes racing essentially unplayable

Screenshots

Log files SimHub.1.txt

Specifically, the error happened at around the 23:40 mark

Additional context I have reseated all of the fans connections to the motherboard and fan controller and my USB connections, and the issue is still not resolved

[SHWotever]

Hi ! Thanks for the log, I can confirm I see the usb devices failing, Including some completely unrelated devices such as your Simmon shifter. This clearly appears to be usb instabilities. If you spread the load to many usb ports you can already exclude that possibility.

Usually if the usb spreading is not the cause, the second one will be EMI a bad usb cable. Eventually it could be a faulty device causing shorts or similar things. I would try to exclude them one by one to see which on is the cause.

NB : DD1 is well known to create some heavy emi, emi are often causing issues to other devices, and are mostly only visible when they are used (simhub running and connected to the devices)

You have a full guide about usb issues available here : https://github.com/SHWotever/SimHub/wiki/USB-Issues-Troubleshooting .

I see that you have

[mr-big3]

Hi,

Thanks for the update. I actually just tested to see if the issue would occur with the DD1 off and Simhub open, and it just happened, so I don't think the issue would be EMI. Does this mean it would be a cable issue? I've attached the log, it happened at 2:00 SimHub.txt

[mr-big3]

One more update: just happened again at 2:05 while my PC was idling, just simhub open, no games. This issue also doesn't happen when I don't have simhub open, should I reinstall the software as well? SimHub.txt

[SHWotever]

Hi ! I see the same pattern lot of devices lost, this clearly goes in the same hardware direction. Reinstalling simhub won't help in that matter.

If you have some good usb3 powered hub around I would recommend to move the most consuming devices to it like the screen. If it happens even when idling EMI could be excluded too, that leaves basic usb instabilities (motherboard not able to power all at once or reaching limits, or a bad usb cable.

When devices are not used they mostly don't interfere with the system except notifying disconnects. Overall Simhub just uses your devices and that's where the issue will show. If they are not in use (no audio, no communication) 99% of the time such issues won't show as pretty much nothing is sent over usb.

Usually just one faulty device is enough to cause "usb"-calypse, In the current logs I can see devices of any kind failing so it's hard to pinpoint a specific one, If it's not a motherboard usb issue itself, that's why I was recommending to unplug the devices one by one to locate the faulty one.

[mr-big3]

Hi,

After several days of testing every USB device, the issue is still occurring. I am convinced that the issue must have something to do with how simhub recognizes or communicates with the devices. With simhub closed, the usb devices have not disconnected a singular time, and I have monitored the computer for more than 12 hours. With simhub open, the disconnections will happen at least happen once an hour, and often more.