Latency Issue OS X 10.8 Cubase 7

Hi, I recently bought Cubase 7 and I really enjoy it :smiley: . Although, there is something I can not solve. The latency issue. I compose film music, so I’m using a lot of instrument tracks with Kontakt 5. Additionally I use some Reverb form 2Caudio on several Fx tracks. I have a mac mini with intel core I7 quad core 3.7 ghz with turbo boost, 16 Go 1600 Mhz DDR3 My system is on a SSD with over 500 m/sec read and write. The libraries are on a Lacie 2 big thunderbolt Raid 0 with 320 m/sec read and write. I recently made an orchestral Template just with Kontakt. It’s about 60 instrument tracks, with like 4 fx tracks with just 2caudio reverb on it. With that Template the minimum buffer I can use is 1024. At 512 I have audio dropouts on every note I play on the instruments tracks. So I’m condamned to work with a latency of 24 ms. :confused: We all know that you can notice latency when it’s over 6ms. I’ve been working on Logic for years And even today on same machine with the same template on Logic I can work with a buffer of 512 even 256 !! So why ? How can I solve this ? The drivers of my sound card Impact Twin from TC Electronic are up to date and the sound card is on low latency mode. I’ve tried other mode and it’s not changing anything.
I’m hoping you guys can help, :unamused: