Getting a cheap Lanzar amp to work well

Running a tl494 based “1000w” lanzar htg237 dual channel amp in bridged mode, hooked up with a in-phase xt8 sub.

Im having an issue, where tones played through my 8” 2ohm dvc(wired to act as a 4ohm load)shake my room perfectly, however when playing songs, at over half volume the sub begins to sound muddy and looses any depth.

Apart from the fact that its a cheap, cheap amp: could these be issues:
The amp is supplied with a 12v 360w smps power supply. I cant find any bridged rms rating for this amp, apart from “1000w max”. Does this mean i need a 1000w power supply? I highly doubt the amp could hit this high, with how its been performing so far, so i feel like as an educated guess it probably cant go over 400wrms.
Bass boost is set to 0db
Amp gets significantly hot considering that it could be being underpowered
The led on the amp tends to dim quite a bit at loud volume during music, however is fine when tones are played.