Audio Systems: Crackling speaker, legacy amp, ac voltmeter

Question
I have an american legacy amp and i just installed it and is making my door speackers crackle... i  hooked the door speakers up to my other amp thats in there and they didnt crackle...  could the american legacy be hooked up wrong? or is it bad?

Answer
It could be wrong gain settings or just too much power.

Don't exceed the RMS of any speaker by more than 10%.

The purpose of the gain is to match the signal volts RMS coming from the source (CD player, etc.) to the input of the amp.

Here is a guide that will help you set the gain correctly http://www.datafilehost.com/download.php?file=6d26c621

You'll need a multi-meter (AC voltmeter), Microsoft Excel and a way to burn an audio CD from an MP3.

If you don't have Excel, use this link http://www.box.net/shared/nkkw1dhk4g