Backing Up Hyper-V Virtual Machines Using Sysmantec Backup Exec 12.5 for Windows Servers

Hi,

I am taking my virtual machine daily backup by using Symantec Backup Exec 12.5 for windows servers’ software. The backup is running very fast in initial days (1700mb/sec) but after few days, the backup is going slow down (200 - 300mb/sec).

Why it is happening? What can I do to improving my backup speed (1700mb/sec)?

Please post your solutions ASAP

Thanks in Advance

Regards,
Babu Kumbhala