TrueCrypt transfer from Drobo is very slow

I’m having a problem where older data on my Drobo reads very slowly. I’m getting about 2 MB/s when reading from the Drobo to my computer for large files. I think this is due to the data being encrypted so the Drobo doesn’t know what should and shouldn’t be sequential and it spreads the file randomly across multiple drives.

That one piece of the story, but here is what gives me hope. When I transfer a slow file I I get 2 MB/s. When I transfer a new file to the Drobo and immediately back, I get 30 MB/s which is maxing out my computer disk. The problem is if I then try to transfer the slow file, both will drop down to 2 MB/s. Is the Drobo really that busy or is there some software setting that’s doing this?

I posted a question to this forum which lead me to this conclusion.

Apparently, if I first copy the files from my encrypted drive to a new folder in the same encrypted drive it fixes it.