I bought two, both popped. The sound came from the left side middle of both of the iPad Air 2's. the screen flickered from time to time and was not responsive. It popped when ever I scrolled through it or while I was on the Internet, using design apps! sending emails, it popped intermediatly. I called Apple Business Team and they said it sounds like a hardware issue and I could mail it back or take it to an Apple Store for a refund. They never mentioned an exchange. I took them to an Apple Store they said it is a Hardware issue and apologized then they offered me a refund. I bought an MacBook Air 13", i7. A nice addition to our company.
I Received a follow up call a few days ago from an iOS Senior Advisor and they suggested now is a good time to buy an iPad Air 2. We went and picked up two. So far no problems. We both use them for work. Sun up to sun down and then some; and no flickering, pops, blank screens, or just glitchy stuff what so ever. Well, besides the regular glitchy 8.1.1 stuff. We were told we have 30 day's instead of 14 due to the "holiday" return policy so we will be putting them to the test. We have a lot of events to coordinate so we will be really pushing them. We use a lot of graphic design apps and communicate quite a bit with them with our clients and employees so we really love the continuity. If all goes well we will upgrade our employees iPad Mini 3's.
One last point if it was a software issue Apple would have a fix by now. Try to remember software fixes especially firmware or drivers are easy fixes and if it were the speakers why would Apple deny that. Point is we had the exact same problem but we took it straight back to Apple and we never mentioned speakers just the facts. There is a popping noise coming From the back left middle, and the screen was unresponsive and they flickered, etc... They took them to the back and straight away stated quit plainly it was a hardware issue.
WHen you call Apple and tell them the speakers are not working correctly and you send it in to Apple they will look at the speakers due to how their repair center operates and if it is not they will return it due to there is not a problem with the speakers. But if you tell them all of the problems associated with your device they will check all those things. That is how they work. Keep in mind they have thousands of returned product for repairs not to mention refurbished devices.
I Wish everyone the best and please don't shoot the messenger and if Apple is denying this is a problem oh well, that is their issue. If you decided to hang on to your popping device well I hope the very best for you and maybe you can convince Apple to refund or exchange it. I believe the best advice to give someone regarding this issue is to return it. Keeping a broken device doesn't help you or the system.