WD Backup Interferes With ITunes

WD External Drives External Drives for PC
1

As of the most recent update to ITunes for XP (10.0.1.22), the playback of my music library is interrupted when WD Backup is running.  The interruptions last from 1 to 5 seconds, and are apparently random.  The interruptions stop immediately when I shut down WD Backup.  The WD Backup version is 4.00.5484.

I’m a newby here…any thoughts?  Thanks.