Audio tracks and Song Mode Sequnces

How do the audio tracks relate to sequences in Song Mode? I mean we can start with Seq1 than Seq 4 and then Seq 1 again and so on. But the audio tracks how will they play in relation to sequences in Song Mode? How do we control them like we control the sequences??

Thanks a lot!

The hard recorder only works in song mode so they go along with song.
You make the song or song outline and then record the hard drive tracks.