I am sure it did go into protection. There are just too many amps in these modern receivers, powered by inadequate power supplies.
Members, you really need to look at specs and understand them and be much more careful about what you purchase.
Just take a look at this spec, copied from that receiver's manufacturers speck sheet.
Power Output (6 ohm, 1 kHz, 0.7% 2ch Drive) | 165 W |
Power Output (6 ohm, 1 kHz, 10% 1ch Drive) | 235 W |
There are NO specs quoted for more than two channels driven. You don't have to guess why, you know.
So that means that the power supply is so undersized as to be useless except at low to moderate volume. No specs are given for using more than two channels. But you can extrapolate that the receiver will be woefully deficient in power if four or more channels are used. So I can be certain this power supply was overloaded and went into protection. In any event the power supply has a maximum power draw of 700 watts. Of that at most 450 watts will be available to the speakers total, at the most, and may well be less.
It is totally dishonest to have a nine channel device and only quote a power spec. for two channels driven. Few will buy a receiver with 9 channels to power a 2 channel system. But honestly that is all that receiver is fit for.
In current program there is actually a lot of power going to speakers other then the front three, as the OP has found out. This was something discussed on a recent Audioholics video presentation.
That receiver is only fit for low spl. usage. I would never recommend anyone purchase a unit with that specification for high spl. levels at any time.