digirack delay plugin adding distortion?

[j20056]

I have a perfectly clean stereo flanged guitar signal. Using stereo busses, I added a slap delay, a long delay and DVerb, for a total of 3x2 bus channels.
What I noticed is that the wet signal has some type of distortion, kind of like when you saturate analog pres, or something. I checked that I am not hitting the reds in the plugins.
Has anyone experienced this? Are the digirack effects such low quality? I was thinking about getting Waves anyway, but I figured I might give the free plugins a shot first.