Spike suppression arrestor for PC speakers?

I notice that when I turn on my wimpy 1 watt USB powered speakers for my PC, there will be a somewhat loud spike noise which may damage them. This also happens when I boot up the computer (I never turn off the speakers).
I was curious to find out if some sort of surge or spike arrestor would help eliminate this spike noise. I think I need to connect a varistor inline between the pos. and neg. lines, but not sure if that would work.

More info here:
http://www.cinemasource.com/products/power_conditioners/about/circuit.jpeg

from:
Power Conditioners

Jeff

It would be cheaper and probably better just to use the money to buy better computer speakers.