Are you using the stock wires for the radio. Could be that when you draw enough current the radio shuts down. How many batteries are you running? How is the system wired? A little more info would help.

Two batteries and yes, the standard wires that the boat was wired with.

I would upgrade your wiring. You can run the best speakers around but if your wiring isn't upgraded and your tuning isn't done right it will sound like crap. Trust me you can get so much more out of your system if it is tuned right. Adam at Saccenti marine can really tune a system and set it up right.

Yep new wires dedicated for the radio and amplifier is what you want. Factory going through the buss will always give you trouble.

Speaker wires are probably fine, unless they did a common ground, but I have only ever seen that done in a checkmate.

Setup is very much the key. Can't tell you how many times I have seen a system with the gains on the amp's wide open. They are not volume controlls they are there to set the output of the radio to the amplifier.

Having the proper power for the speakers, setting the gains correctly, proper crossover points, proper speaker placement, correct box for subs all will all make a huge difference in sound. Most people are very suprised at the sound I get from my 200 watt system, with only 2 sets of no name component speakers, and relatively inexpensive P-1 subs.

you mite need more wattage i have 4 rockford 6.2 under the back seat and 1 rockford p2 12' in a vt box in the bow with 800 watts and it riples the water all around the boat sound great you need at least 800 to 1200 watts

I had the same problem with mine cutting out at higher levels.

it was a stock speaker shorting out when pushed hard, making the amp flicker into protection mode. swapped in new 6.5 and its started rocking.

then added some 6X9 and even better. and i could adjust the amp better becasue it was not cutting out.

also speaker box on subs, make a HUGE difference.

I'll try disconnecting the stock speakers for starters and see if that makes a difference.

Thanks To all for the input.

Ray