I have built some tracks and when I play them back I get a double sound on the instruments eg two basses and two pianos.
It has happened using _LAZYJAZ.STY
I have turned the volume down on the bass and a bass still sounds!!!
Any ideas how to fix this problem?

In the BIAB mixer top right....
Click on Audio lower right....
Play the BIAB music.
If audio is active...
Then Mute the audio track...

If it sounds good....
Render new wav file.

This could be your glitch...

Good Luck!