Hi guys I got some serious issues here. I know that this topic has been discussed a lot already but I think my issues are somewhat different. I got a MacPro 2x2,8 Quad Xeon with 10 Gb of 800Mhz DDR2 Ram running the latest Leopard and Lion on two different Harddisks. Working on recent projects I constantly came across CPU spikes on core8 in the Logic System Usage Window leading to crackleNoise & DropOuts on both systems. Always thought that it might have to do with Plugins like Trilian, Kontakt Libraries etc... Now I decided to do a test and I loaded like 8 to 10 instances of The EXSPiano Hall Preset and let each play a four note chord progression simultaneously. 7 of the 8 cores go spiking red 1 (Nr 7) is almost never active (same on SL & Lion) then I went to my Macbook 13. 2.4GHz Intel Core 2 Duo, 4Gb 1067Mhz Ram running Lion and did the same - surprisingly the Dualcore CPU can handle like 12-14 instances without spiking. whatÂ´s going on with my Mac Pro? Any Ideas ThankÂ´s in advance.