Although the Micro BR is a four track recorder, and therefore only capable of four tracks of simultaneous playback, each track does actually consist of eight V-tracks(virtual tracks.)
The first audio that you record on any of the four tracks is V-track 1. (TR1-V1, TR2-V1, TR3-V1, TR4-V1) If you record a take on a track and you decide that you want to record an alternate take without erasing the first take, then you can change the V-track for that channel and then record a new take. You can later decide which is the best take for playback or you can copy the best part of each V-track to a completely new V-track.
You are also using a V-track other tha V-1 when you bounce your four tracks down to a stereo pair. You will notice that when you first go to bounce mode the destination for your bounce is TR12 V-2

To change a V-track, use the following steps;

1. Press TR1.

2. CURSOR to the right several times to access the VTrack screen.

3. Press the TR1,TR2,TR3 or TR4 that you want to change V-track for.

4. Use the VALUE buttons to switch to an unused V-track.
Note-A Square that is filled in already contains data. An empty square indicates an empty V-track.

5. Press EXIT.