Tracks out of synch

I finish a project (song), bounce down to a mixdown track, send that mixdown track to mp3 converter and listen to it on a different player. The Drum track is way too loud in the mix when it wasn't on my workstation.
Also, when I go back to the project, the mixdown sounds the same but when I mute that and run the individual tracks, they are out of synch. What am I doing wrong?
 
I am in HS6, and with reverb and delay, btw.