MR 816x is not recognized by Mac

Hi ,
I have a big issue , i m using os x 10.6.8 and MR is not recognized , i downloaded and tried Tools for MR v1.7.2-2 but result is same , driver installation is normal , i can see “Yamaha Steinberg FW” on “System Preferences” menu after the install , but i can not see any device on this menu (and audio midi setup menu) when i clicked on. I tried many things to solve that problem like purchasing a new FW cable , installation from older versions etc. Now i m downloading mac osx 10.6.8 update combo ,i hope it can fix , i need your help seriously , i want to connect this device to my mac , what should i do ? waiting your suggestions. Peace.