Synchronous video reading from seven port USB3.0 HUB

I want to read synchronous image from seven port USB3.0 HUB connected to Jetson TX2. I have 7 cameras in total. The resolution of each of my cameras is 640x512. So the bandwidth is sufficient. Each port of the HUB supports 1.5A, so there should be no power problem. When I plug in the cameras and look under /dev, the cameras randomly sometimes see it, sometimes not. It seems that the file under /dev is not updated when I plug in the cable of each camera to the HUB. When jetson tx2 reboots, the cameras come on, but after a while, some cameras start to go. I made usbcore.autosuspend=-1 to avoid autosuspend error. The system seems to be a little more stable, but the problem persists. What could be the source of the problem?

This use-case(one USB3 roothub + 7 cameras) is not tested, so it is possible the setup is not stable. Are the 7 cameras all USB3 cameras or it mixes with USB2 + USB3 cameras? Do you use Jetpack 4.6.2?

On TX2 developer kit, you may consider use PCIe to USB card and move some cameras to the PCIe port. Or use a custom board which has 2(or 3) USB roothubs.

The cameras are all USB3.0. Since I am working on a rotary system, I move the cameras from the HUB to the tx2 with the help of Slip Rİng. In this case, there is only one USB output on the Slip Rİng and I cannot use it separately as PCIe and USB. I have to solve the problem as USB only. The interesting thing is that even if I connect 4 cameras or 3 cameras on the HUB, I can encounter similar errors. Therefore, I do not think there is a problem with the number of cameras.