After SP3, Backup job need two tapes to complete

Hello everybody.

i have 5 servers using BE 2010 R3 SP2, after upgrade SP3, two of that server need two tapes to complete a job, that with SP2 only need one tape.

The tape drive is a LTO 2, and the tapes are of 400 GB, the size of the Backup Job is 260/270 GB in one server and 330/340 GB in the other one.

i think that this SP3 make several changes that affect compress of the data, i dont know.

Somebody has been similar issues?

I´m thinking go back to SP2 in that servers.