Has anyone noticed any issues when using their iPP when plugged in? I've tried a few different cords, power sources, and with or without keyboard. After a few minutes of normal work (email, web browsing, Google Docs, M$ Docs, etc.) my iPP starts to hang and becomes unresponsive. I know some people have had issues when their iPP is plugged in for awhile so I'm wondering if this is another symptom of that root issue.