In the last day or so play back of MP3s (music, notifications, etc) has started to sound really bizarre, basically it sounds like someone is slowing down a vinyl record. The effect does not occur at the same point during playback, nor does it sound exactly the same each time an MP3 is played back. * It happens with built-in notification sounds, and those I've added. Also happens with music MP3's. * It doesn't seem to have any effect on call quality, nor on the call ring-tone I use when a call comes in, although if I try to playback the ringtone sound it happens. * It happens when using the Music app, and when an clock alarm triggers. * I tried stop most/all services. No change. * There is no visible damage to the copper speaker cover. Anyone experienced this before, or know what the cause, and fix, might be?