my speakers hum

Because you are trying to play music to songs they don't know the words to.... Badum dum! :)

Sorry.

Can you describe the speakers that do hum? Are they particularly efficient? or powered?

Usually it's your cable TV or a connection to a PC.  Try disconnecting it, if any, and see if the problem continues. If so, I have a solution for you. :)

Best,

Erik

Unless your speakers are self-powered, they can't create their own hum.   

the speakers are audio physic tempo. no tv. no computer connection.