Speaker question
speakers usually fail bacause of high bass input not treble. It just sounds like the treble because the frequencies are more audible.
usually the best bang for your buck speakers are infinities or whatever els you can find on ebay.
one common problem is that if you went from a system that had a factory amplifier then the speaker impedance will be lower than the normal 4 ohms that the radio uses. This will result in distortion at higher volumes. It could also be a shorted speaker lead and finally as noted it could be the bass is set higher than the speaker can handle...



