very slow down load onto Lacie hard drive from Time Machine from my macbook
I have a Macbook pro running Yosemite 10.10.2. I also have a Lacie 1T external hard drive. I haven't backed up for a year (not good I know) and in the interim, I upgraded to Yosemite. I connect to my Macbook from a Firewire 400 lead to a Thunderbolt adaptor (which I did last time, no problems) only now, the download speed is so slow as to be useless. What might be the cause of this other than a problem with the hard drive?
MacBook Pro, OS X Yosemite (10.10.2)