Loud pop on startup

I have an OEM Entune headunit I've been trying to upgrade. First installed Infinty Reference component speakers up front, immediately followed by an Alpine 45 watt amp. Sounded better but the highs were piercing, the bass was OK, but the mid-range was really hollow. I recently installed an LCQ-1 line out converter/equalizer and Infinity Kappa speakers in the rear (Access Cab) doors. Now I'm getting a loud pop when the igntion key is turned on, not previously heard prior to installing the LCQ-1.

Both the LCQ-1 and the amp are grounded to hard metal ground points. The power to the LCQ-1 is tied to the headunit positive, the amp is tied to the LCQ-1 remote out.

Any ideas what's causing the pop?

 

The LCQ-1 probably shouldn't be on the same circuit as the head unit. That may not be the issue though, but it started happening when you installed it, right? You could try a few things. First, the lcq again really should get its power elsewhere - say...from where the amp gets power. You could try grounding everything at the same location - all your audio gear...head unit, amp, lc1...everything. You could go a step further and ground everything at the battery. If that doesn't do it, you can delay the amp turn-on so that the pop happens before your amp switches on. Or replace the lcq.

 

Is this a JBL or non-JBL system?

 

Non-JBL