There must be some conflict with my system or something. I keep losing sound to my speakers when I'm watching videos or listening to music. I'll watch a video and everything is working fine then I click on another one and it has trouble loading and I can't listen to my Yahoo music after this happens either. I'm getting a low hum usually when this occurs in my speakers.

I got some new speakers and they are not working I don't know if it is my sound card?

Could be, but try pushing the cord into your computer. For example, my speaker's cord keeps popping out of my laptop as if it doesn't fit. It does this with headsets and everything. It will barely come out but I still lose my sound. And it is annoying because if I just tap it it will pop out. So try holding it in and see what happens.