Hello AJ
Some points you should know about USB
1. The USB Ports on your Laptop are isolated from each other.
2. When you plug in a hub, the available resources are shared, which means if every item was working, then you would only have a quarter of the speed available for each item.
3. If you plug a USB 1 device into a USB 2 Hub, the hub will drop down to USB 1 speeds for all the ports. (Mouse and Midi Keyboards are normally USB 1)
To maintain the speed you require, I would suggest that you plug the hard drive and Soundcard directly into the laptop, and the Mouse and Keyboard into the Hub.
Hope this helps

Bill