Thanks for not giving up! I really appreciate it.
You can view the power consumption of each device plugged into the USB port in the Power tab of the Hub properties. This information comes from the device and is not calculated by the computer. As a result, this is sometimes inaccurate or an estimate by the designer, but at least it's an indicator.
Thanks for the suggestion, cdanteek. It's unchecked (on all of them).
To make 100% sure it's not a power issue, the Roxio is on a USB 3.0 port since (900mA) and the same problem happened on it as well.
The only thing I can think of is that there might be something wrong with the HDMI input signal from Xbox to Roxio or from Roxio to monitor. That's hard to test without moving the entire setup to the downstairs TV, but the Xbox was plugged into the monitor for ages and it always worked just fine. So I'm thinking either the Roxio is not giving out the input signal correctly or the monitor is not picking it up. Actually, the latter can't be it, as I don't get a signal in the software either.
As you forums vets never heard of this problem before, I'm thinking of returning it and getting a new one.