STRINGS: (only for electric bass): selects the number of strings of the bass (5, 4 or 6) 5 string gets you down to B, use 'Drop' to go 1 step lower to A.
Thank you, I did read that section and found that the issue was actually the midi file I was exporting from GuitarPro. I learned that it tends to be transposed by one whole octave below.
Once I learned that, I was able to get the correct tuning.