I noticed this morning that I received some e-mails and didn't hear the notification sound. I then tried changing my ringer and noticed none of them were playing. I then tried playing a video and there was no sound either. Under Settings -> Sound -> Volume, the volume settings for Ringtone, Media, and Alarm are all up all the way. The phone is not on silent. I also tried restarting the phone, plugging headphones in and taking them out, putting the phone on silent and then back to normal, all to no avail. When I plug in headphones, I can hear sound through the headphones, and when I make a call, the earpiece works fine, but speakerphone does not, so it seems like the speaker on the phone itself is broken. Oh, I should also mention that I haven't rooted my phone or anything like that and the apps I've installed shouldn't affect sound (Yelp, Facebook, Flixster, IMDB, USA Today, Engadget, etc...). Has anyone else experienced a similar issue? Is there a setting that I am missing? Or is this a hardware issue?