Computer speakers receive radio station signal

Solution 1:

It's probably your cables picking up the signal from a transmitter that is close to your home. Usually this is caused by folded cables (Like when you neatly tie them together). If you have folded cables or lots of cables tied together, try if unfolding them or seperating the speaker cable from the rest helps.

Solution 2:

Whoa, trippy dude!

I assume that your audio cable (comp -> amp) is acting like an antenna. It seems surprising that it picks up only one station instead of a few at the same time, that is very selective. Drastically changing the shape or length of the cable should wreck your "antenna" ;)

I would build a low pass RC filter with a cutoff around 1 MHz. For example: R = 160 ohms, C = 1 nF according to an online filter calculator. Or you could buy a filter I guess. It may be sold as a noise suppressor, they are used in car audio installation. Install it at the receiving end of the problem cable.

You could instead wrap the cable in tinfoil, and ground it to the (metal?) computer chassis.

If all else fails, just do what the voices tell you to do. YMMV.