Firewire My Studio 1TB keeps removing itself from desktop

I am running the MyStudio on Smartware 1.2.2.5 I am using Timemachine for backups and not the SmartWare version. Each time the computer sleeps the hard drive unmounts itself from the desktop and I need to manually mount it. This is a problem in that several hours of backups are missed and I could potentially be in trouble if this happens. Is there anyway of keeping the drive from unmounting itself?

Thanks.