i took a 4:30 minute video the other night and at about 3:30 it apparently stopped recording the sound. has this happened to anyone? i was at an insanely loud party and the audio seems to stop roughly when it got really loud during the last few minutes of the show. i am speculating there may be some type of protection in the iphone to stop recording the sound if it reaches a certain volume level. or maybe the audio is still there and it's just not playing it back because of the same reason?