I run a 2x 15’s 3:1 blow through box in my truck and usually around 155db’s 3 days ago it was fine and had been for almost a year no issues but today it is hard to tell they are even there so quiet that my mid ranges muffle them
The first thing you should do is double-check all of your wiring connections. Usually when people come to me with this issue it's a loose ground or a bad RCA cable.
If everything is snug, grab a multimeter and set it to Voltage AC and probe the RCAs going to the amp and the speaker leads. Depending on your head unit/DSP, you should get anywhere from 2-6v at full volume on the RCA.
Since you said you're capable of 155 db, it's clear that you have some decent power. Voltage = ✓(watts x impedance). With this is mind, probe the speaker leads and see what voltage you're getting. 3000 watts is about 54 volts @ 1 ohm, for reference.