Happens all the time for me. Sometimes the music just stutters, sometimes the music goes to a different part of the track. Happens via Aux and Airplay too. Pretty bad bug for us avid music listeners.
Saw the title and thought it was going to be the "album art cover is displaying incorrectly for a second before it shows the right one when a song is playing" bug. LOL.
It happens to me, but not all the time. I think its when I tried to use the scrubber to go back on a song (which is useless by the way, even in the actual app), it kept going back to a certain point. The only way to stop it was to restart the phone.