"Big" has nothing to do with it. You've got 8 speakers and a woofer wire to a 4 channel amp with a dead chnl. By shifting a couple of speakers over to another chnls, you have wired the amp with an impedance thats lower than its designed operating parameter. This can and likely will, cause the amp to cycle off when the volume is turned up. However, this will not cause the head unit to cycle off, unless some of those speakers are wired to the head unit and youve doubled up one of the head unit chnls with two speakers.

So, I would return the wiring to how it was, confirm the dead chnl or bad spaker(s) and any other faulty equipment. Then replace as needed.

With 6 in-boats, 2 tower pods and a woofer, You either need two amps or need to shift some of the in-boats to the head unit, if they are not already there. I would suggest a 2 chnl amp for the tower pods and a 5 or 6 chnl for the woofer and 6 in-boats.