OK, ever since I became an iPhone user four years ago, I've been using the default email tone when receiving emails. However, I decided to change to a new tone with iOS 7 GM. I'm now using the "Chord" tone. However, I've found that sometimes (usually when the phone is locked) it will play the old default new mail tone. However, when I'm using the phone or in the Mail.app itself, it will play the "Chord" tone like it's supposed to. This is the only tone that screws up for me. Any idea on where to begin in troubleshooting this?