buy a Yamaha LOL all kidding aside I am not sure you can do a single track you can try Keyboard transpose on yamaha you have a choice in the mixing con section to set song to transpose and keyboard stay in orig key as well as a single track .
I think Korg has a challange in this area this is a concern of mins=e as well.
why are you transposing -5 on 1 track and all the other stay the same I think you would want all to be in the same key and then use the transpose to move the whole song up or down like a capo would do on a guitar I use this regulary on my Tyros to play in guitar frendly keys .
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