Fixing the Otterbox Echo Phenomenon

I recently purchased an Otterbox Defender case for my shiny new Galaxy Note 2 from AT&T. I like it a lot - it's durable, sturdy, and the holster doesn't break off all the time like those annoying $6 cases you can get from that site that begins with "Am" and ends with "azon."  But .. there's always a but.

As soon as I installed the case and made a phone call, the person on the other end complained that they were hearing a loud, obnoxious echo of themselves speaking. This basically rendered the phone useless for what is supposed to be its primary function: making actual phone calls!  So, I went immediately to Google to do some research.

It turns out, a lot of people experience this problem, not only with Otterbox cases, and not only with the Note 2. I read reports of the same behavior with the Galaxy S3, iPhone 5, Galaxy S2, Motorola Droid whatever, HTC phones .. the list goes on and on and on and on.  Sidebar:  That last bit is better if you sing it like a grunge rock song.

So, what to do about this?  Well, Otterbox says it's the fault of the phone and not their case, citing numerous users of the same product that don't experience the issue.  All the carriers are either silent, or say that, since the issue shows up when you add the case, it must be the case's fault. Neither is going to do anything about it except point fingers at the other and leave their customers hung out to dry.  Thanks.  Jerks.

Not satisfied with the corporate buck-passing, I decided to take things into my own hands. I'm an engineer, after all, I should be able to solve this problem. And indeed I have. In fact, this solution highlights the fact that I am a messed up combination of engineer, redneck, and former wanna-be musician.

The Earplugs

The idea is to acoustically isolate the primary microphone (the one you speak into) from the rest of the phone, and especially the earpiece speaker.  To do this, you'll need the following materials:

1. Some disposable foam ear-plugs. The kind you squash and stick directly into your ear. You can usually find them at your local shooting range, usually for free if you spend some time on the range (which I highly recommend).

2. A good, SHARP pocket knife. No, seriously - if it's not sharp enough to shave your arm hairs with minimal pressure, then sharpen it until it is - then sharpen it some more. If you don't have a pocket knife, a good sharp scalpel, art or surgical, will do.

Sliced

First, use your sharp knife to slice off the wide edge of one of your ear-plugs, making the slice as thin as you can make it. A fraction of a millimeter is all it takes.  Actually, do this twice. In order to have uniformly sized slices, I used two separate earplugs. If the earplugs you find are not the tapered kind, you can use the same one twice. What matters is that you end up with 2 thin slices of earplug foam, which you'll use to surround the primary mic pinhole of your phone.

Next, use your sharp pointy thing to cut a very small opening into the very center of each slice. This opening needs only to be 1 to 1.5mm in diameter, and it can be square or whatever shape you end up with. You just have to make sure you actually physically remove some of the material - simply poking a hole isn't enough. The material has to be able to fully expand and retain the opening.  UPDATE:  I've found that a hand-held hole punch is perfect for this part of the task. It leaves a nice big hole making it much easier to align with the mic, too.

Hole poked and Applied to Phone
note the mic pinhole is visible

Now, take one of your perforated slices and fit it over your phone, leaving the hole over the primary microphone opening in your phone as shown.

Back in the hard shell. See the mic?
Pay no attention to the
weirdo behind the phone

With the slice in place, fit the phone back into the hard shell. Make sure you can still see the primary microphone's pinhole in the phone, otherwise no one will hear you when you make calls. I found that it took quite a bit of fiddling (and some cursing and swearing) to make sure the shell closed completely while leaving the microphone exposed. If you have a Note 2 like me, you can use the stylus to finesse the foam a little once it's closed in order to accomplish this. I presume some other pointy object like a pushpin could also suffice.

Everything back on. See the mic?
Yeah, me neither. I had to re-do it.

Now, take one of your slices and fit it to the bottom microphone hole on the inner (hard) shell of your Otterbox. I had to trim one side of mine because it ran up against the porthole for the USB charger. Again, you have have to make sure that the opening in your slice is over the opening of the hard case, which is over the opening of the first slice, which is over the primary mic's pinhole. With this in place, fit the outer rubber shell of your Otterbox onto your phone. Once again, this will be tricky and your profanity skills will likely be called upon. At the end of the process, you should still be able to see all the way to the primary mic pinhole.

Finally, you're done. Make a test call, preferably to someone who's complained frequently of the echo problem. If they don't hear the echo, you're done.  If they do .. well .. please post here and let me know, and feel free to try something different. Remember - it's more likely to work if you swear at it.

Just for Fun - the finished product*
*feel the swagger

Remember, this solution is specific to the Samsung Galaxy Note 2 in an Otterbox Defender case. However, the main principle should apply to any phone/case combination. If you're reading this post, you are probably smart enough to adapt it to your specific situation, so please feel free.  Good luck!