Protection circuit activated on two different receivers

Hi guys,
My parents bought a house a few years ago that has a home theater of sorts in the basement. The original setup was a Yamaha RX-V992 receiver, PSB front and center speakers, a powered sub that says "Velodyne DLS", and two white surround speakers mounted to the ceiling that I can't identify. At some point, the receiver started shutting down when there was a really loud noise in the movie. In the Dark Knight, for example, it might shut down when the bank teller walks out of his office and shoots his shot gun in the first chapter.

We were told that the receiver was busted, so we basically just used the system a lot less from that point on. Recently, I bought my dad an Onkyo TX-NR609 for his birthday and fathers day. After some setup, however, the same issue persisted.

Do you guys have any advice for troubleshooting this? We are having some real difficulties getting past this issue. One thing worth noting is that when we were using the audyssey setup, the front right speaker sounded a bit quieter than the others. We also have the receiver and a few other items inside of a wooden box in a cabinet that slides in and out a bit, and my father was concerned that the track may have frayed the wire. I took a look and did not see anything.

Thanks in advance for any advice you might have.

Thanks for the tips. The wiring is all through these grey cables, each of which contains red and black positive and negative cables. The previous owner of the house had all of it run through the ceiling and walls, so very little of it is exposed. The sub has two cables which are similar to rca cables that run through the walls as well. If I was to find an ohm meter, would it be a valid test to use it on the two sub cables, or would I have to do something different to check the sub wiring?

Thanks for the advice.

The AVR probably has about an inch of clearance on either side and a solid 6 inches above it. The front of the cabinet is open. The fact that it always happens at the same times (specific loud noises) makes me want to believe that it is not a heat issue. It will happen two minutes after we turn the receiver on, if we can get to that part of the movie fast enough.

Checking the wire all the way from the receiver to the speaker will be difficult, if not impossible, given that it is in the wall. I might have to try that as a last resort.

If I use an ohm meter, what is the best way to test the wiring? Shuold I leave it connected to the speaker and test the ends that would normally be connected to the receiver?

Well, I connected just the front three, then I added surround left and right, and there were no issues.

My dad has now also told me that he was having an issue with the sub where pulling the receivers gliding shelf out by some amount would cause it to hum, and he suspected that it was something with the connection. This was while using the old receiver. The sub connects to the receiver with two coax cables that have RCA ends. Do you guys think that this could be implicated? The receiver was hooked up and positioned in a way that I did not hear the hum, but after he mentioned it, we were able to replicate it.

We think we may have figured it out, but we would love to hear if the solution makes sense to you guys that actually know about this sort of thing. The sub, which has its own power source, was turned all the way down. The audyssey setup had it turned up some db (forget how many), and my dad suggested that those big booms might by sending out too much power when the sub could actually be doing some of the lifting on its own. We turned the knob on the sub to halfway and then reran audyssey, which set it to -12db. We then replayed the scene that we watched earlier and got through it with absolutely no issues. We even got past that part to an even louder boom and again had no issues.

Does this make sense? We are going to keep an eye on it, obviously, but it has passed the first test. I have no idea how it came to be set up that way, though. The issue was not always present, so I have a feeling that my parents got to fiddling with knobs at some point and inadvertantly did this.

Will do, thanks!

No idea, dude. Sorry. Do you have a powered sub, and if so, did you try what worked for me?