Tech issue with music playback on iPhone

I got a new computer so I transferred my iTunes library via Firewire/Thunderbolt- had some extensive issues but sorted them out and re-organized my library.

When I did my sync from the new library to my phone, it cleared, and replaced everything as its supposed to.

So the music is back on my phone but many songs stop midway through and start playing another song from the album or just go mute.

Example: Song 1 playing, audio stops and Song 2 starts. Phone still says Song 1 is playing. When the display does change to Song 2, it picks up where it left off from the previous track instead of starting new.

So I need my music to play properly on my phone. I thought maybe the files got corrupted during transfer but its fine in iTunes and its happens to random songs after each sync.