[Swimmer]

I have these speakers and a whatchamacallit base box in the middle that yurn on when powered up, but have never transmitted any sound from my computor, which is where I am using them. I have had them for years. Never cared to hear anything sound-wise coming from the computor until now. They appear to be attached properly. Plugged in, power light comes on, but no voice sound when watching a video except from the flat screen speakers. What do I need to do?