Five disks chained together is asking for trouble. Consider getting a SATA array of at least 2TB.
Check System Preferences to make sure you don't have any Sleep or Energy Saver options activated on your computer. For digital editing, you should NEVER put any of your drives to sleep.
Lacies do get clumsy if you leave them on for prolonged periods of time. Reduce the number of drives in your chain to improve performance.