[FutureTrooper85]

So I swapped out a bunch of my factory speakers about two months back on my '09 FA5 for a set of Alpine SPS-600 (rear) and SPS-600c components (front). They worked fine minus a little bit of noise from the amp integration method. A few days ago I finally got my Alpine PDX-5 amp, hooked it up, and to my surprise everything worked perfectly the first time around...for about a day. I can now hear a cracking that sounds like it's coming from the front left tweeter, it's the kind of sound I would imagine you would hear if the speaker was blown.

What's weird is that I can only hear this sound when the car is moving (and even then sometime it won't kick in until a minute or two after I start driving or it will come and go while driving). The second I come to a complete stop, even if the car is running, it will go away completely. I swapped the outputs for the speakers on the amplifier and sure enough the sound traveled from the front left tweeter to the front right. So does that mean there's a bad channel on my amp?

Any help would be greatly appreciated, I'm thinking the amp is the problem but since this was my first amp install I thought it might be a good idea to get some 8th knowledge thrown on me first. If it makes any difference I don't listen to my music loud at all, I used the amp bypass harness rather than running new speaker wire, and as far as I can tell I have a good ground.

One last thing, when I received the amp it was missing it's "birth certificate" along with a few of the hex keys. I contacted the seller I bought it from (a very highly rated seller on Amazon) and he stated that either alpine left it out by mistake or I was accidentally shipped a returned amp from another customer. In either case he will exchange it without any problem if I so desire.

 

[onyxaltezza]

I had that same issue a while ago, i just rewired the parts.

Check your grounds, make sure no wires are grounding out against the chassis, etc, and make sure none of your wires are crimped. My issue turned out that the wire to the tweeter was crimped, causing it to go on/off constantly. It was getting pretty annoying lol

 

[FutureTrooper85]

Thanks for the reply. I think I actually narrowed the problem down to a bad RCA wire. Basically, one of my cables was about 2 feet too short so I used two female-female connectors I had lying around the house with an old RCA cable to add that last few feet. Apparently this wasn't a very stable connection so the speaker would go in and out or just buzz, mostly when the car was moving and thus vibrating. I literally just finished running a new (longer) RCA cable and it appears that fixed the problem. Hopefully that'll fix everything but if not I'll be sure to update.

All that's left to do is mount my free-air 8" sub in the factory location and my install is complete!

 

[onyxaltezza]

Ah, a bad RCA also was one of my past problems. Mine was weird, speaker would go on and off, so basically the RCA cable was only working when it was bent/angled a certain way. When I took turns and the cable moved around, it would go off, then back on as soon as I was off the on/offramp, etc.