Hi,
What form of compression are you using? Hardware or software?
If hardware, you could try upgrading the firmware of the device. Please note that if hardware compression is used, Backup Exec just commands the device to use hardware compression. The rest is done by the device itself. Hence the need to upgrade drivers and the firmware to the latest version. The following Technotes might prove useful to you:
http://seer.support.veritas.com/docs/199542.htm
http://seer.support.veritas.com/docs/249090.htm
If you are using software compression, please check on the amount of data that is being backed up. Split the jobs and then verify the result.
I hope this helps!
Thanks!!
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