I've been mucking around with piggy tracker a lot these days. One thing which really bothers me, is with lower-tuned samples, when using the volume command there's a noticeable distortion, or perhaps loss of resolution. I made a very simple test comparing piggy to a manually volume ramped (in ocenaudio) 808 kick.
https://soundcloud.com/metrodub/lgpt-distortion
This is on the OSX version.