alpine 4channel

im not too good with sound quality issues so i need advice.  i came across an alpine 4channel amp its MRV-F306 i think is the model.  its a flex4 model alpine, i guess its a few years old.  well anyway i have infinity reference 6.5's front and rear in my Jeep and this morning i installed the 4channel on them.  it sounded awesome until later on today i noticed a weird crackle/pop coming out of them at high volumes.  im wondering if this is cause of the amp or am i turning them up too loud?  the amp only does 40x4 so its not too much power and i dont hear any distortion.  if i keep the volume at the same level but turn the mid and treb down on my headunit to all the way down, the problem goes away but of course the speakers sound crappy. im confused.  could this be bad RCA's? bad amp?  i know its not a certain spekaer that is messed up cause all 4 of them do it.  its very hard to notice, most of my friends have no idea what im talkin about cause they dont hear it but i can hear it and its annoying, not to mention im worried im damaging something.  like i said i dont know much about sound quality so any help is appreciated..thanks!

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sometimes speakers will do this when they are trying to produce bass that they are not made for try setting the crosover. you could also reset the gains on your amp.its really hard to say i have only had this problem with smaller speakers, those 6.5 should sound very good and have a good bass response, you could try putting a bass blocker on them and see if this helps

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i worked on it a lil tonite.  it wasnt the bass that was causing the problem..the tweet was clipping badly.  i turned the gains down quite a bit on my head unit.  my HU has 5volt outputs but i thought it was only on the sub, didnt realize the front and rear also has 5v.  so i turned the gains on my amp down from 3/4 up to just under halfway up and it made all the difference..still very loud but now it is crystal clear and no clipping.

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