We have a client that uses Seagate Barracudas between a Sonic System and Protools and of course SAonic doesn't see a Protools (Mac) formatted drive. Sonic uses its own formatting style but as soon as the drive is reformatted with the Sonic utility all is well. Never had to change any jumpers to get it to work on Sonic.
Hope that helps,
Mike Thornton (One Stop Digital (OSD) Ltd
www.osd-uk.com