Crack sound´s with ANA

I bought the ANA synth and when i use it with Cubase 5, even if it´s just one synth and i make a beat, and add some other instruments from other vst the ANA vst seem´s to make my sound crack down until it start´s to slow down everything until i remove it, i put the buffer size up but that doesn´t seem to work any tips on how to fix this ? i got the system requirements for the synth so don´t know what the problem could be cause this dosn´t happen with massive kontakt sylenth1 or nexus. :pinch:

What are your system specs?

Windows 7 home premiumbr
processor: AMD ATHLON™ II X2 220 2.80 GHzbr
Ram 4,00 GBbr
64-BIT OPERATING SYSTEMbr

do you have a soundcard?br
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If you are using onboard sound this can really slow the CPU down.br
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Your CPU is rated at 2251 on geekbench.br
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My mac laptop is about 8000 and Desktop 13500 for example.br
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