Norton Ghost 14 / XP - Incremental Recovery points take a long time

Hi,

 

I am running Windows XP, SP3 and Norton Ghost, backing up to an external USB hard drive.

 

I run a full back up monthly with incremental recovery points daily. Initially, the incremental recovery points took 10 minutes, now they take over an hour, with no significant increase in data.

 

Any thoughts on what has changed / going on? This is a pain as Norton then hogs the processor and slows the system down....

 

I have tried slowing down the backup speed, but, the incremental recovery point then takes all day....

 

Thanks

Dave