Hi there. Ever since I have my Macbook Pro I am having an issue here. I do use my Macbook as desktop in clamshell mode very often, and I use a USB hub for my external keyboard, mouse, headset and webcam, which always worked fine on my Windows PC. Now, the problem I have is that when I am using my Macbook with the USB hub, I the USB hub (or atleast the devices that are connected to it) stops working for one second, like it is resetting. For example, when I am going through some videos on YouTube, and I start or stop watching a video, I can hear my headphone turning off for a second, and then the sound will switch to the built in speakers, which is very annoying. So it only appears to happen when I am doing stuff, like browsing. What makes it even more strange is when I have continuous sound on (like a Skype call), it doesn't turn off/reset the devices on the USB hub, and stays just on without any problems. Also, it doesn't seem to be a hardware issue, since it doesn't happen at all when I am running Windows on my Macbook. So, might it be some energy-saving setting that is causing this? if yes, where can I disable it? Would appreciate your help & suggestions. Thanks!