pca3500d in protection mode

   I tuned a soundstream picasso 3500d to 77.45 volts with an 40Hz sine wave for running two dvc 2ohm digital design 3512c subs, which were wired with the voice coils in series and the subs in parallel.   Within a half hour or so of playing with the new toy, it decided to go into protection, throw in alternator whine for a few seconds, and pulse the subs apparently in reverse excursion...I quickly shut everything off, but noticed this all as I was listening and observing the subs for tonal accuracy.    After removing the sub wires, and RCA inputs, the amp is obviously blown as it will not come out of protection mode. I happened to hear from someone about these brand new amps having a common problem with an internal component...and I was wondering if anyone is familiar with this situation. And is it a cap, diode, resistor, etc. Please elaborate, thanks. makinwavesMakinWaves

Just to clarify, when I used the sine wave, that was with no outputs, except the 10Mohm multimeter. Luckily, I do know better than that....lol. All I know is the amp sounded like it was getting DC voltage on the AC side, no smoke, nothing that would indicate a short, the voice coils were cool, and everything works fine with my old amp(temporarily).   There is about 5volt input signal going to the amp.   Even more, to ensure I had the proper power going to the amp, I turned on my headlamps while it was "pounding" about 143dB and the didn't dim at all, so without taking measurements there yet, I assume it had a minimum 12volts. Regardless, I already have installed a second battery with an isolator for the future. Apparently, I must have received a faulty amp. Time will tell with it's replacement.MakinWaves