A mystery for you tech gurus out there

Z, than you simply SUCK as a dealer AND manufacturer. Many of those like you will loose business just because you will refuse to give to audition your product for a couple of weeks or even to support your client that apperently encountered the problem like an OP. Even Wyred4Sound 15% restocking fee seems to have much better statement than you've just quoted. I will see the future of giant Best Buy overtaking all of your measurable business to start selling Martin Logans, Maggies, Dyns, Krells Macs and other high performance audio equipment including analogue in the near future just because they're not thinking like you and they're not going to throw me out of the customer list.
Is it dishonest to ask BB rep if there's a possibiliity??? Guess now what kind of answer do you expect to hear from BB rep or have you EVER heard one?? Exactly the answer they've been trained to give as a customer rep of Best Buy. I haven't seen them in HT department specifically that they're not happy to assist you at any of your request. Perhaps to better improve your dealer skills you should fill out an application and work at least part time to get a hands-on experience on customer service. I guess it might help running your business better.
If you think one way all the time, you won't be able to solve any problems(LOL even elementary school equations) and wouldn't be able to even stand for the product you manufacture or sell.
Please remember that there's not only length, but width, depth and height. Your math is horrible especially when you try to speak in terms of profits... As I said, find more learning resources before dogmatizing your righteouseness.

I agree with Zydo about the source's as the popping occurs at any and all inputs ... also agree with Zydo that it isn’t the speakers as the popping stays with the amp's output and does not follow the speaker

I even think your receiver is OK ...

What I think is causing the popping is that amp’s channel is not balanced correctly to the other channels and is putting out a little more power than the rest of the channels ... causing that channel to clip on peaks

This is causing the ...

"occasional, loud pop. Usually the pop comes in bursts, and sounds almost like a fireworks show would with a succession of airy-sounding, concussive pops".

... you are experiencing because the input to that amp is set to high relative to the others amp's inputs in the set up menu

Try turning the main volume down 20% and see if the popping continues ... if it stops then that amp is clipping and needs to be readjusted in the menu ... if the popping continues even at the much lower volume ... I would suspect an issue with the receiver

Maximum capacity is a rating ... not a challenge

.

+1 Davehrab, you may have just salvaged this thread with a note of clarity for the original qn. If the OP hasn't abandoned in frustration, I suspect that he'll know by now whose hijacking posts he should just ignore.

The original description suggested possible clipping to me as well, but I couldn't envision what might cause this in a single channel for a solid state amp. The channel balancing issue might just be the solution, but in general, I wonder what else could be at play?

Is it possible that someone needs to brush up on their Dale Carnegie? The question does assume that the person wants to be liked by others. Anyway, here's a brief synopsis of some of Mr. Carnegie's most core techniques.

Fundamental Techniques in Handling People --
Don't criticize, condemn, or complain. Give honest and sincere appreciation. Arouse in the other person an eager want. Never show others that you are not interested in what they have to say.

Twelve Ways to Win People to Your Way of Thinking --
The only way to get the best of an argument is to avoid it. Show respect for the other person's opinions. Never say "You're Wrong." If you're wrong, admit it quickly and emphatically. Begin in a friendly way. Start with questions to which the other person will answer yes. Let the other person do a great deal of the talking. Let the other person feel the idea is his or hers. Try honestly to see things from the other person's point of view. Be sympathetic with the other person's ideas and desires. Appeal to the nobler motives. Dramatize your ideas. Throw down a challenge.

Regarding the OP, it could be some outside electrical interference being picked up by a interconnect/cable on the left channel. Try repositioning.

Sandstone ... this is what qued me

-Denon 1913-AVR receiver

It's a HT receiver not 2 channel receiver and requires balancing of input signal to all channels including sub for balanced response

Turn one channel’s input up a little to much in relation to the others and it will clip before the others

OP descript sounded like clipping to me

.