ProChannel should not introduce unwanted artifacts unless it is overdriven. Can overamp any eq especially midrange and get dirt, more distortion, clipping, overdrive as an artifact from Sonar being pressed beyond what it was supposed to do. Not the fault of the eq, and any DAW will crap out in the extreme, so not the fault of the DAW either..
Still stand by an incredible gem in the eq arsenal. Use it more for pre processing than on the output end, but doesn't get much better than this IMHO. Free offering for the taking. Resurrecting the dark force "R" word. ReaEQ is in there with the installation suite and should be in the tool kit of every digital musician. Get it here:
http://www.reaper.fm/reaplugs/ Cannot argue about the price, regardless of what is politically correct about "R".
John