AVPlayer - Add Seconds to CMTime

elegant way is using CMTimeAdd

CMTime currentTime = music.currentTime;
CMTime timeToAdd   = CMTimeMakeWithSeconds(5,1);

CMTime resultTime  = CMTimeAdd(currentTime,timeToAdd);

//then hopefully 
[music seekToTime:resultTime];

to your edit: you can create CMTime struct by these ways

CMTimeMake
CMTimeMakeFromDictionary
CMTimeMakeWithEpoch
CMTimeMakeWithSeconds

more @: https://developer.apple.com/library/mac/#documentation/CoreMedia/Reference/CMTime/Reference/reference.html

Here is one way:

CMTimeMakeWithSeconds(CMTimeGetSeconds(music.currentTime) + 5, music.currentTime.timescale);