Well its the speakers that killed the receiver almost certainly. I can now outline the sorry tale I have long suspected and tried to explain.
The latest receivers are NOT 4 ohm stable. Receivers years ago where not and for many years to the recent past they were and now they are not. They are just stable to 6 ohms.
Your speakers are rated as 8 ohm nominal. They are not 8 ohm speakers but actually BELOW 4 ohms effectively.
We are at the point now where you should not connect speakers to recent receivers and unless you know the impedance curve and phase angles between voltage and current. If you don't know then you need to invest in a Dayton woofer tester to measure them.
Now the next thing is on this and other forums we continually teach that speakers like yours with a high sensitivity rating will be OK, as they will take little power. WRONG.
Now the good folks at Home Theater Review have a good set of measurements in a well done review of your speakers.
This is the measurement section.
Here are the impedance curves and phase angles of your right and left mains.
Now you have to understand that a speaker transitiosn from being a monopole to an omni directional radiator at a frequency determined by the width of the front baffle. The narrower the higher the frequency is. So in order that the speakers do not sound thin then the frequencies below that transition have to be boosted. The only way that can happen is for the power to be boosted below that frequency. In a speaker with a passive crossover the only way to do that is to drop the impedance. This is called baffle step compensation, BSC for short.
You can see this in the graph. At 150 Hz the impedance of your speakers is 3.1 ohms. But the phase angle is still quite negative at that point, so current draws will actually be higher than simple calculation would imply, as there is a gap between true power and apparent power. Unfortunately the higher apparent demands will be higher than the true demands, but the current required for the apparent demands have to be met.
Now you can see that the impedance starts to drop below around 800 Hz. This is BSC kicking in.
Now sensitivity ratings are done with a specified voltage. Now you can see that at 150 Hz the speaker will demand five times the power from the amplifier at 150 Hz than it will at 1 KHz for the same sound pressure level.
Now things are still against us. In music peak power demands are in that 80 to 1.5 KHz range and truly peak in the usual range of the BSC.
Now another myth is that subs off load speakers they don't. First of all the power demanded by music drops off below 80 Hz. Even more importantly you can see from the impedance curve, that the two tuning peaks of impedance occur in sub range, actually making power and and current demands modest. What subs do do is offload speakers by reducing cone excursion.
So you see things are not actually like you have been told by dealers, manufacturers and forums, including this one.
So, now we have receivers where so much of the funds are going to licensing and complex processing, with far too little not only spent on power amps but the space devoted to them.
A cheap power amp will not be known for longevity.
We would be far better off encouraging manufacturers to make pre pros, which if produced in quantity would be cheaper than receivers. Investment in a good power amp is a wise investment. Good looked after power amps can last a lifetime and do not become obsolete.
So my final advice to you is to purchase good external amplification for your front three speakers and use the preouts on your receiver when you get it back. Otherwise I fear you will be back in the same boat.
If you get the impression I think receivers are a lousy idea, you are correct. I have explained my reasons above.
Unfortunately for you it is a classic example of the falsehoods frequently spouted on forums like this.