I am on a PC but I remember having to re-enter some settings on my RME and ASIO preferences after the initial move to WL8. Hope that helps.
12th & Vine Post
Intel i7 860 at 2.8GHz, 4 GB platinum memory RAM, ASUS P7855D E-Evo, Windows 7 Professional, 3X SATA internal (Seagate/Raptor) and 2X firewire HD, 2X external DVD drives: Plextor/Pioneer, RME HDSPe AIO, Mytek converters
WaveLab 8.5 current release, iLok, Waves, DMG (Dave Gamble), Sony Oxford, Weiss, Class A Solid State and Custom Stuff