logic and error with sample rate when using exeternal fw drive
 

hi, I am a new mac user, i own an m audio 1814 fw card, and just bought a lacie 500 gb rugged model, (with 3 interfaces, fw 400 and 800 and usb) (LaCie - Rugged Hard Disk - FireWire 800, FireWire 400 e Hi-Speed USB 2.0)

i set up on my macbook pro, in fw chain, mac book-lacie- m audio, i opened logic and try to run a project of 16 tracks stored on lacie, but i had error with sample rate, it reads 46056, and after stop and play it reads another value,
both hard disk and audio card are power supplied,
now a inverted the order, i set up first audio card and at the end the lacie and it seems it works, but i would like to understand why i got this problems