Time Machine - Why the slow transfer rates all of a sudden?

[BadboyHouse]

I run a Time Machine backup every weekend to an external USB drive.

Usually the transfer rate is at least about 40 - 50 MB or higher.

I did a backup today, before installing the 10.7.3 update and the transfer rate fluctuated from about 1MB to say 20MB. Much slower than normal.

After installing the update I ran another backup, and it's transfer rate is around 1MB per second.

Is there any way of finding out why it's gone so slow?

 

[Macman45]

I had this after the Combo update. I rebooted my TC and everything went back to normal again.

 

[BadboyHouse]

It was actually pretty slow before I installed the combo update.

But interestingly, the backup I ran after the update (which was about 3GB) was really slow (1MB per second) up until the 2GB point. After that it shot up to 3GB in a matter of seconds.

It's no big deal - it's backing up I will have to be patient.

 

[Macman45]

You might want to think about getting that TC checked...Only other reason for it being slow is a poor wifi connection if you are not hardwired.

My MBP and my MBA use wifi and they are a lot faster than that. If you have warranty left I'd get it checked.