Solving USB Problems

USB is at the heart of most PC‑based studios. But what do you do when it goes wrong?

The Universal Serial Bus — USB for short — may have become the most ubiquitous connection standard found in everyday use. Since its creation almost three decades ago, and over four generations, it has been implemented within many electronic devices we take for granted in everyday life. Each successive generation has increased bandwidth and, in many cases, power delivery. At the same time, they have all been designed to offer backwards compatibility with previous generations, making USB devices from different eras as interchangeable as possible (at least on paper). However, things can still go wrong, and, depending on the situation, there are various steps you can take to help rectify the problem. Let us take a look at the different ways we can approach USB issues on Windows machines.

Starting with the hardware connection, the worst‑case scenario is that you plug in a USB device and the PC switches off or subsequently refuses to switch on. In this case, you should check for physical damage. Look inside the USB port itself, as this symptom may be the result of the pins inside the socket being bent out of alignment, causing the system to short out when the USB cable pushes them further together.

If you plug the device into a known working USB port and the system fails to detect that you have done so (no new item appears within the Windows Device Manager), then we would tend to expect either a connection or physical issue which may lie outside of the system.

The first step would be to try an alternative USB port, preferably switching from the rear to the front (or vice versa) of the computer where possible. The rear ports are generally native to the system chipset, whilst the front ports tend to be supplied via third‑party controllers, often resulting in differing behaviour between the two sets. You may also find a couple of USB 2.0 ports on the rear of the system, as many mainboards still ship with a dedicated pair, to help maintain support for particularly picky older hardware.

Power Move

Switching out the USB cable itself, and testing on a second computer, are both steps that could help you to narrow down where the problem lies. Upon connection, if you receive a Windows warning stating “unknown USB device needs more power than the port can supply” and the device has the option to add its own power source, then now is the ideal time to double‑check that it is connected and powering the unit as required. Power delivery is also a good reason to avoid USB hubs without their own dedicated power source, as USB hubs powered solely by the PC connection will be limited to dividing up one port’s worth of power across however many hub‑connected devices are in use.

However, if you only have an unpowered hub to work with, it’s worth noting that newer USB generations offer improved power delivery. For example, the USB 2.0 specification allows hosts to deliver a total power output of 2.5 Watts, whereas USB 3.0 and 3.1 allow for a total of 4.5W, and the latest USB 4.0 standard increases this to a potential 240W delivery when EPR or Extended Power Range functionality is implemented. So, simply switching over to a newer‑generation port may help resolve issues with power delivery.

As well as dividing data bandwidth, unpowered USB hubs also share only a single port’s worth of power between all the devices connected to them. If power delivery is an issue, try connecting unpowered hubs to newer‑gen USB ports on your computer, as these tend to have increased power capacity.

Cable length should also be a consideration. To achieve the best performance, both USB 1 and 2 had recommended maximum cable lengths of 5 metres. This dropped to 3m with USB 3.0, and USB 4.0 lowered the limit again, with the older Gen 2 (20Gbps) running at its best with cables up to 2m and the latest Gen 3 (40Gbps) implementation listing just under a metre at 80cm.

This isn’t to say a longer cable won’t work, but you can expect a potential...