Yip,

Yamaha Service representative did send me an Email, confirmed the USB problems (low speed and occasional disconnects) are known to Yamaha and investigation for solution is ongoing.

If I have more information I will post it. Also some other TYROS owners have contact with Yamaha and will keep me/us updated.

Anyway if you find yourself the speed and/or unreliabel USB connection a problem also inform your dealer, the number counts always.