Possible Clues:

• Belt of ocean calm
• Ancient musical instruments found outside equatorial area
• They won't get the wind up if they get mature drink into them
• Listless despondency
• Rhythm's about vintage blues
• Percussion instruments to convey familiar feeling of gloom
• With mature spirits in them they won't get the wind up
• Blues
• Belt of calms in equatorial oceans
• Belt of calms and unpredictable weather in equatorial seas