[Volo Ganca] "could this be the Drobo's fault?"
It could be since Dropped Frames are caused by FCP not being able to retrieve data fast enough from the storage device.
We only use our Drobos for storage/backup, we don't edit off them. Use something like a G-RAID or G-Speed for editing.
Rob Grauert, Jr.
http://www.robgrauert.com
command-r.tumblr.com