Hello Kip,

Some of the comments in this thread are incorrect.

First, I tested your project file and the distortion is definitely there and sounds terrible, especially on the Guitar tracks. This is an artifact caused by Reaper pitch shifting and tempo stretching the wave files.

You can fix this by going to File | Project Settings and setting the pitch shifting method to Elastique Pro 3. It's possible there are other parameters here which you can set. Try the defaults (see attached image).

With the Reaper Instructions feature, it's Reaper that does a lot of the 'processing' of the raw wave files. If you weren't using Reaper Instructions, then it would be Band-in-a-Box doing the tempo stretching and any additional processing, and it would be giving you one long wave file for each track, all ready to go. Each method has pros and cons.

So DrDan is more or less correctly describing the feature, but didn't identify the cause of the distortion, while I think Musocity is talking about the concept of the BiaB DAW plugin in general.

Attached Files (Click to download or enlarge) (Only available when you are logged in)
reaper_projectsettings.png (2.1 KB, 62 downloads)
Andrew
PG Music Inc.