All three speakers just started fading at the same time and the right channel makes a lot of noise. But I've been out of the audio loop a long time (the speakers in question are nearly 10 years old) - who are good manufacturers? Harmon/Kardon? Klipsch? Boston Acoustics? Someone else?
My amplifier is a Yamaha RX-V663 and the TV it's hooked up to is a 55" Mitsubishi.