Trouble with system, Any idea?

[2Dcore]

K, I put my system together and it sounded awesome for what it is 4 10" alpine r's ran by Kicker kx2500.1 Ran up to 2ohm's sounded good for a month than i noticed it wasn't hitting as hard and kind of muffled almost distorted sounding but still hit somewhat than out of the blue it will started hitting again almost sounds like what it does when out of phase but it's not i checked everything but it did seem to start when i put 2 new amps in for mids and highs. Any thoughts on what could be going on? Bad ground do this? Thank you

[itsblown]

Voltage drop

[mylows10]

bad ground ,not enough juice ,pick your poison

[2Dcore]

no voltage drop it doesn't do it all the time it slams than maybe a day or so it might do it again i keep a meter on it to see volts 13.6-12.4 est.

[2Dcore]

Plenty of juice for 2500rms 2 kinetic 2400's big 3 alt is stock but no bad drop. it doesn't drop out when it's working correctly it will hit for days but when it goes it will last for days.