AIX Image Backup Performance Issue

I am running 3 simultaneous image backup jobs on an AIX server and the HBA only shows 20% utilized and my throughput sucks. I am using -imagetype=static and the FS's in questions are EMC clones split off and remounted to a new server. When I have done image backups before they were wicked fast...now not so much. Any ideas what I might have missed? I have an ACSLS STK 8500 with LTO-3 drives. Even over gig-ether I've seen better performance. We did check the CPU and memory usage and they are fine. Lots of I/O wait, not sure why I would see that with statc image backups.