E5410 LED indicator causes pops over external soundcard

Hi, I am using a Hifi audio external soundcard over USB, but on my E5410 it gets serious pops whenever the Storage Drive LED indicator flashes blue (i.e., the little blue cylinder next to the battery and wifi indicators). The soundcard works fine on other computers. I've tried various usb slots, and they all have the same effect. The indicator blinks every 1 or 2 seconds, regardless of what I am doing. My understanding is that it flashes whenever there is a read write to the harddrive. My question: is there a way to temporarily diasble the LED? Or is this just a red-herring. Its a real shame. I am using Ubuntu 14.04 with uptodate bios and vanilla linux kernel in Real-Time mode. Thanks