Problem with the Sound system in my corolla

[celica2004]

HI there,

I recently brought a 1993 toyota corolla. The other day, I noticed that the right speaker in my car is not functioning. I tried to balance the sound in both the speakers. When I turn the balance knob completely towards right, I hear no sound at all.. I can hear sound in the left speaker, but there is lots of noise present.

Can any one tell me the procedure to diagnose the reason of this strange behavior of the sound system.

Hope to hear soon from u guys..

Thanks,

new carollate.