MIDI Controllers freezing or losing connection

Live versions: All
Operating System: All

MIDI controller USB connection issues can cause the following problems:

To fix this, please try the following steps:

Replace the USB cable. For best performance, use a short, high quality USB cable with a ferrite bead. Just one faulty or underperforming cable can sometimes knock out USB connection for all other USB devices currently connected to the computer.
Connect directly to the computer's USB port and not through a hub.
Try different ports on the computer - some devices don't work in USB 3.0 ports.
If using a hub, it must be powered. Check that the hub is functioning correctly and that its connection cable is also working properly. A hub's overall speed is automatically downgraded to the speed of the lowest performing device connected to it. For instance, if you plug a USB 1 device into it, all other devices on the hub are downgraded to USB 1 speed.
If using Windows make sure that power saving is disabled for USB ports.

If you're still having issues, check the following:

If using a MIDI controller with a control surface, make sure that you've configured it correctly in Live's MIDI preferences. Check that the correct ports are selected and there is only one Control Surface active for the same controller.
Make sure that the drivers and firmware of the USB device are fully updated (where applicable).
If you've recently upgraded your operating system, check that the device is supported on the new OS.