my music cuts out at higher volumes

[king alpha 0]

I've owned my car for over 10 years, and went through 3 alpine head units, and went from a pair of JL 12W6v1s to a single SI Mag and from a 600W Crossfire amp to a 880W Massive amp. I've always had a problem when I play bass heavy songs where the song would "skip" (actually, it stops playing for a split second) when the volume's at 16 (The gains were set by ear at 15 and I would never hear distortion with the gain knob 3/4 around. And I always turn it back to less then 1/2, because my ears can tell if it was distorting). I always thought it was the amp going into protect, but I just realized that the whole song skips and not just the bass. I'm thinking if the sub amp is going into protect because it's a bass heavy song, the front amp should still be fine and I would still have mids and highs. So, I'm guessing it may be the head unit skipping from the bass vibrating it or something. I really can't think of anything else. Anyone have any idea why it cuts out? I want to know because I have a feeling this Mag that I have can get a bunch louder.

[Tirefryr 1,742]

Low voltage, loose ground, could be a myriad of things.