Mystery voice in MixMaster?

[BogdanH]

Hello,
My question is actually addressed to MixMaster creator, but anyone with an answer is welcome...

I have a style (no idea from where), which has voice 127-0-80 defined in it. I checked many DataLists (Tyros4+5, Genos and all PSR since 2010) and this voice isn't listed in any of them (btw. I could find this voice listed in Yamaha CVP202 DataList).
If I open that style in MixMaster, voice is named as "StandardKit", however only for Tyros+Genos keyboards -for all PSR keyboards this voice is "unknown".
Now I wonder, how come this voice is recognized as built-in for Tyros+Genos keyboards?

Bogdan