RMAN Performance Problems following Platinum Patching on Exadata DB

I backup my dev,tst and prod databases (9 in all) to ZFS on two RAC servers on an Exadata 1/8 rack machine. Prior to quarterly patching, our backups were set up in 30 minute intervals and each completed in that amount of time.

After Platinum Services patched our DB Homes and Grid Home, RMAN jobs slowed to 4.5 hours each. I had to cancel incremental backups on my three test databases. Even with that, RMAN backups run all day, 24 hours a day. They still run into each other. I opened a support ticket but response has been slow and not very helpful.

I have tried a few things to no avail. 1) I spaced the backups so that they would not run into each other and cancelled the incremental test backups. 2) I changed the parallel processes in RMAN configuration to 8. 3) A colleague and I looked at settings that existed before the patching and changed a couple of things. I would have to ask her for specific changes.

I am curious if anyone has experienced something similar and what you may have done to get these backups back to normal execution times.