As I previously mentioned, I think the case has improved a lot since the original IP4 version. My IP4 case was so bad that after three replacements, I asked for a full refund which they did. With my IP5 version, I have some issues such as the humming when on a call, vibrating back if volume too loud, and occasional complaints while on call or speakerphone. The vibrating back issue, I resolved by placing a small thin felt piece (just about the size of the area below the window and inside of the ribbing) between the backplate and the phone. This keeps the backplate from vibrating on the phone and also seemed to help a little with the call and speakerphone issue. I noticed that if I turned down the speakerphone volume, then didn't have as many complaints about echoing or not being able to hear me. Also, if worse comes to worse, you could just open the port door and use the phone fine. For me, most of this was minor considering that the case is shock and water resistant and in a relatively small/thin case.
This morning, I decided to try to see if perhaps I can get a newer version under warranty and see if I can have these issues improved upon. I contacted Lifeproof by phone and had to wait about 30 mins to get through, but I got through and they took care of me. I've never had any problems with their customer service and today wasn't any different. Hopefully, the newer version really makes the case better. As long as it is as good as the one I have, now, I will still be happy with it. Just trying to see if the newer version gets rid of some of those issues.