[That7guy]

I just installed a Alpine SPS-171A speakers, Pioneer Premier DEH-P770MP HU and a Visonik V408XT amp and it sounds great. The only problem is when the RPM goes above 4500 it starts to buzz and crack like something is interfering with the signals. It also does this at WOT. What do you think is causing this and what can fix it? Could it not be grounded enough becasue when I was wiring up the equilizers I lost one of the screws so I put two of the grounds in one connection. Could that be the problem? Also when I get in the car and start it, the spreakers pop before they start playing. Ive heard this is bad. What did i do wrong?
Please help, I know next to nothing about sound systems.
7

 

[AMMendes]

That is ground loop. Is ther sound like buzer going up? Does also happen when you pull to ger some water on the winshield? Is yes that ara some ground not correct.