USB problems with new PC build

My nephew is finishing up a new build and says everything works fine but the USBs are twitchy, almost like a loose connection but he’s checked several times.
I know this is very little to go on but are there some common errors he should be on the lookout for?

Define twitchy. Difficulty establishing connection or intermittent connect/disconnect of device with no cable movement? One device or multiple devices and what types of devices? USB ports on motherboard or pin connector on motherboard to cable to case mounted ports? All ports or some ports?

Multiple mouse clicks with one press, keyboard keys sticking…

I’m not there so it’s hard, we’re texting.

He’s trying to reinstall drivers…fingers crossed…

Most importantly, are the keyboard and mouse plugged into the USB ports on the motherboard, or external cable-connected USB ports?

What drivers is he reinstalling?

Does it work if he tries one device at a time? I had to move my wireless mouse dongle from the back to the front one day because the twitchyness got to be too bad.

Needed new USB 3 drivers for the mouse & KB - all fixed!

That’s good news, but HID devices (keyboards and mice) typically don’t need anything but the most basic USB 1.0 support to work. That a USB 3.0 driver had to be installed/replaced to make them work reliably points out the weirdness of modern USB chipsets. These are scary times.

Assuming he’s using the motherboard’s built-in ports, is this Intel or AMD?