I have a pr4400 when you try to select the crossovers on either high or low pass it sqeals I only have one speaker on it also it makes the speaker pop
Could be defective, bad ground situation, head unit. First thing I would try, turn the amount on, recreate negative sound. Low volume. Now take a short piece of wire touch one end to the ground connection for the amp, and the other end touch to ground connection on rca (that's the outside ring) if it stops. Shut everything off, disconnect your negative battery terminal from the vehicles battery. Now go back over every bit of your wire job. Verify you have the correct wire size for length ran and projected amp draw.
Also, check every connection, power and ground, and not just on your amp, check the ones under the hood. Don't wrench then, just try to unscrew it with your hand. If you can, duh.
This will not only improve sounds quality, but it will save you cash. Bad connections drain battery, tired battery needs more help, helpful alternate gets tired, if alternator does not keep battery in top condition, starter starts to prematurely wear. Those three items are $500 and that's just parts.
Also, if the amp starved for ground, it will find one, at the RCA. Will burn up cable and fry the outputs on the radio. There is all the tools you need to succeed. Let me know what you find.
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