Help OBS not seeing multiple cameras on a multi USB Dock.

[Kev kinch]

So I have a Lenovo laptop thinkpad Gen 1 with windows 11 and a seperate USB-c Expander docking port 48W with plenty of speed, made by VKUSAR.

(All 3 web cams are different makes & models BTW).

Now when using ‘windows camera’ App I can see all 3 cameras running fine when they are all connected on separate USB ports on the one USB dock expander which is plugged in to one of the USB -C ports on the laptop all 3 cameras work with no issues at all with ‘Windows Camera’ app.

But when I close the ‘windows Camera’ app and open OBS (despite previously setting up OBS to have all 3 cameras on it), OBS will only display 1 camera and not the other 2 cameras.
If I unplug 2 cameras and re-boot OBS it will see a camera that wasn’t being seen before, in no particular order, but not all 3 at anytime Together via the docking station ports.

If I plug each camera into a different USB port on the laptop (1 on left USB, 1 right USB and one in via USB-c docking station) then OBS display’s all 3 cameras with no issues, BUT I then have no more usb ports on laptop hence wanting to use the docking station in the 1st place.

Any Ideas?

 

[1.21gigawatts]

I GOT THIS!!! Amazing, but I GOT THIS!!!

This has been an ongoing problem since we started using OBS a few years ago, and I just figured it out this afternoon. We had the same situation. Several cameras plugged into a USB hub, and only one at a time working. The way I fixed it today was to plug each camera into a SEPARATE USB controller.
This particular computer has two front panel USB ports, so ONE camera plugged into a front port.
The rear panel of the computer has USB 3.0 and 2.0 ports, so ONE camera in a USB 3.0 port
ONE camera plugged into a USB 2.0 port on the rear panel
This computer also has a 7-port USB 3.0 card which I was hoping to use for all the cameras, but today, ONE camera plugged into the card.

That's FOUR cameras and they ALL work. I have rebooted several times, I have exited and restarted OBS. The thing just works now, and it never did before.

I'm happy that it's working, but this seems like something OBS ought to be able to handle. I'm not a programmer, I design industrial controls (and I'm pretty much retired from that, too), but we're a quarter of the way through the 21st century...

I hope this helps. Please keep us updated.

 

[koala]

It's quite clear why plugging USB devices into their dedicated port instead of using a hub will work, and because of this it's the recommended approach: it's USB bandwidth. If you use a hub, all data is funneled through the hub connection. If you use USB 2 devices, all USB 2 devices on the hub share one USB 2 bandwidth. Since one USB 2 webcam is able to consume all USB 2 bandwidth for its connection, more than one USB 2 device on the hub congests the USB system.

Even if your hub is connected with USB 3, the USB 2 devices still share one USB 2 bandwidth. Any USB 3 webcam is extra and not shared, but all the USB 2 devices are. It's as if you have 2 hubs in one: one for all the USB 2 devices connected with a USB 2 uplink and one for all the USB 3 devices connected with a USB 3 uplink. This is a peculiarity of how the USB system is designed, no OBS thing.

 

[Kev kinch]

I GOT THIS!!! Amazing, but I GOT THIS!!!

This has been an ongoing problem since we started using OBS a few years ago, and I just figured it out this afternoon. We had the same situation. Several cameras plugged into a USB hub, and only one at a time working. The way I fixed it today was to plug each camera into a SEPARATE USB controller.
This particular computer has two front panel USB ports, so ONE camera plugged into a front port.
The rear panel of the computer has USB 3.0 and 2.0 ports, so ONE camera in a USB 3.0 port
ONE camera plugged into a USB 2.0 port on the rear panel
This computer also has a 7-port USB 3.0 card which I was hoping to use for all the cameras, but today, ONE camera plugged into the card.

That's FOUR cameras and they ALL work. I have rebooted several times, I have exited and restarted OBS. The thing just works now, and it never did before.

I'm happy that it's working, but this seems like something OBS ought to be able to handle. I'm not a programmer, I design industrial controls (and I'm pretty much retired from that, too), but we're a quarter of the way through the 21st century...

I hope this helps. Please keep us updated.

Hi mate, thanks for replying and I should have mentioned that I have also done this and it works, but I just wanted to know if there was a way around it, but seeing another reply to my question below it looks like it’s a no for now,
we have a home PC with more usb ports one usb expander which has everything like keyboard, mouse, lamp, 1 camera only in it and 5 other cameras all in different USB ports and we have run this with OBS for around 5 years every Saturday night for my radio show that is also linked to the station via a codec so we go out on FM as well as MixCloud via OBS, but I am also DJing in Ibiza and last year we said as we link back to the UK via the Codec to do a live radio show on FM lets get a laptop and put the live show on mixcloud whilst in Ibiza + other places to keep all the regulars involved when we are elsewhere.
So my new laptop has only 2 usb’s so it’s very limited & I wanted at least 4 cameras to give a good show, hence buying a docking station (but same issue), then 3 different USB docking stations later I gave up trying and thought I’d ask here,
so currently doing it with 3 cameras + a pants laptop built in camera so 4 at a push, plus with a sound card, mouse etc in the docking station there are cables everywhere!!!
But thanks again for your reply, and thanks to another reply below explaining the whole USB 2 data being swallowed up by just 1 camera, I was hoping there’d be a MAC address solution as all devices have unique MAC addresses but I get it’s still the same issue as the majority of laptops these days have less usb ports than ever, I had to get a usb-C docking station with an RJ45 network plug just to get around the fact that the laptop only has WIFI & pushing so much online via OBS onto Mixcloud needs a hard wired network connection.
I guess I could try a bluetooth option if there is a camera that can connect to the laptop and can still be added as an additional media device…..
Thanks all who have replied so far

 

[Kev kinch]

It's quite clear why plugging USB devices into their dedicated port instead of using a hub will work, and because of this it's the recommended approach: it's USB bandwidth. If you use a hub, all data is funneled through the hub connection. If you use USB 2 devices, all USB 2 devices on the hub share one USB 2 bandwidth. Since one USB 2 webcam is able to consume all USB 2 bandwidth for its connection, more than one USB 2 device on the hub congests the USB system.

Even if your hub is connected with USB 3, the USB 2 devices still share one USB 2 bandwidth. Any USB 3 webcam is extra and not shared, but all the USB 2 devices are. It's as if you have 2 hubs in one: one for all the USB 2 devices connected with a USB 2 uplink and one for all the USB 3 devices connected with a USB 3 uplink. This is a peculiarity of how the USB system is designed, no OBS thing.

Thanks, please so my reply to the first reply above, and if I had of realised this was going to be the same issue as I had 5 years ago on my home PC OBS setup, then I should of got a laptop with as many ports as possible rather than thinking adding a docking station would resolve the issue, thanks for your reply

 

[Kev kinch]

It's quite clear why plugging USB devices into their dedicated port instead of using a hub will work, and because of this it's the recommended approach: it's USB bandwidth. If you use a hub, all data is funneled through the hub connection. If you use USB 2 devices, all USB 2 devices on the hub share one USB 2 bandwidth. Since one USB 2 webcam is able to consume all USB 2 bandwidth for its connection, more than one USB 2 device on the hub congests the USB system.

Even if your hub is connected with USB 3, the USB 2 devices still share one USB 2 bandwidth. Any USB 3 webcam is extra and not shared, but all the USB 2 devices are. It's as if you have 2 hubs in one: one for all the USB 2 devices connected with a USB 2 uplink and one for all the USB 3 devices connected with a USB 3 uplink. This is a peculiarity of how the USB system is designed, no OBS thing.

Thanks for your reply koala

 

[Kev kinch]

I GOT THIS!!! Amazing, but I GOT THIS!!!

This has been an ongoing problem since we started using OBS a few years ago, and I just figured it out this afternoon. We had the same situation. Several cameras plugged into a USB hub, and only one at a time working. The way I fixed it today was to plug each camera into a SEPARATE USB controller.
This particular computer has two front panel USB ports, so ONE camera plugged into a front port.
The rear panel of the computer has USB 3.0 and 2.0 ports, so ONE camera in a USB 3.0 port
ONE camera plugged into a USB 2.0 port on the rear panel
This computer also has a 7-port USB 3.0 card which I was hoping to use for all the cameras, but today, ONE camera plugged into the card.

That's FOUR cameras and they ALL work. I have rebooted several times, I have exited and restarted OBS. The thing just works now, and it never did before.

I'm happy that it's working, but this seems like something OBS ought to be able to handle. I'm not a programmer, I design industrial controls (and I'm pretty much retired from that, too), but we're a quarter of the way through the 21st century...

I hope this helps. Please keep us updated.

Thanks 1.21Gigawatts