Random music cut-off HELP

getpho

So i just got my car and i recently installed a whole new audio system to my car. I got an aftermarket head unit installed,I got 2 amplifiers for my car, one for my subs and one for my front speakers of course. I believe it is an 2 gauge amp wire i used for the positive wire to run from the battery to the amps, and then i have a box splitter, to split the positive wires into the two separate amps. So at first when it was installed it was working perfectly fine but now the high/mid so i clearly assume it is my amp for my front speakers that are either cutting out or not receiving enough power. The car is on of course and it happens when i'm driving. I noticed the battery gauge is jumping sometimes when the bass is hitting. The front speakers do not turn off completely but it is just really low and sounds kind of muffled. I have read about upgrading the alternator but i don't know how much amperage is running from my amps. I'd appreciate the help if someone doesn't mind helping me out on it.
Here are the amplifiers i got: Kicker CX300.4 ; Kicker KX800.1

and my head unit i got it from my old vehicle: JVC KW-NT30HD


Couple of questions: Should i upgrade my positive and negative wires running for my battery?

Do i need to upgrade my alternator?

Let me know if i missed out on any information or anything i may need to do that i can't think of on top of my head right now.