Hi! I've recently noticed that my MBP (10.9.4) sound system crackles while I watch some youtube videos. It doesn't always happens, but when it does I've realized that the CPU fan also tends to make noise (like it's working harder). I've checked the activity monitor and chrome task manager and everything seems just usual, except for high CPU usage when watching a youtube video, something that never happened before even watching HD. How to fix this issue?