Experimenting with it now, using Biab 2019 for Mac (309), I think I can recreate what you experience:

1. Open the Guitar window, Select the Bass track in the Guitar windows, and it correctly displays 4 strings.
2. Close the Guitar window, then open it again.
3. Select the Guitar track within the Guitar window, and it erroneously displays 6 strings but using only the 4 bass strings.

Luckily, the workaround is easy: Just close the Guitar window (while the Guitar track is still selected), then open it up again. It will now display correctly.

Hence I think the problem can be summarized as: If the Guitar window is opened with the Bass track preselected, it won't correctly switch between the Guitar and Bass tracks correctly.

Hope that helps you. PG Music: Will this qualify as a Bug report, or should I formally file a bug elsewhere?

Best regards /Bjorn

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