Sounds to me like that MIDI file you load somehow tells the Tyros to enter a different Mode (which is why it then responds to BiaB differently).
In other words, the problem may not be BiaB behaving differently, but rather the Tyros behaving differently when it receives data from BiaB. I doubt loading something into your keyboard changes BiaB.

In your example the common thing is loading a MIDI file in the Tyros, then both the Tyros and BiaB work fine, so I'm wondering what MIDI message in that file is triggered that changes the Tyros somehow.

'GM On' mode message maybe?
Or Performance .. or?

Last edited by rharv; 12/22/20 02:55 PM.

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