amps and head unit cutting off

I have 2 Kicker l7 15 dual 2 ohm subs and 2 Memphis mcd1000d amps, 1 to each sub. I have a kinetic 1400 and my stock battery with a 200amp IRAGGI alternator. My head unit is an ALPINE ida-x001.  I have done the big 3 upgrade. When i have my level on the amps turned high my head unit and both amps cut off for a few seconds and then come back on. I can turn 1 amp down and the other up high but when i try to match them high it cuts everything off when the bass starts to hit at high volume. I cant figure out what is going on or what i need to do. I have a 20 farad Tsunami capacitor and a yellow top optima battery that i can use also. Also i have a Planet Audio PEQ-10 4 band graphic equalizer I can use. I tried to instal the Equalizer using the same power wires and ground/ remote wired that go to my head unit and the lights on it dim when the bass hits. What can I do?mark

By the way,My car is a 1990 Ford Mustang 5.0 gtmark