I just picked up u-he's Zebra 2 and while it is a good synth certain presets/patches cause crackles in my system.  I have a dedicated daw (no internet, anti-virus or other junk).  I have an AMD 6 core phenom ii 2.9 ghz.  I have a couple of other plugins and everything is running pretty fine.  I'm currently running at 64 samples on a delta 66.  I'm thinking about upgrading to an amd fx 8350 or intel (I know intel is better) but my question is will getting a better processor and the Focusrite 2i2 help with my latency?  I'm going to do some windows 7 64 bit latency optimization later today to see if that helps.  Surprisingly right now money is not an object so I don't mind upgrading.  I'm running Sonar X1 with 8 gb of ram.   

Why not try to up the 64 samples buffer, say 96 or one more notch up and see if the crackles gone, rather than a major hardware change ?

I'll have one setting for low latency recording, another for mixing.  Also freezing tracks can help.

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