i am sorry for my bad english
i can say this thing today , "only one solution is external power supply for your midi keyboard "
i have got 2 different midi keyboard and when i use them with my laptops usb ( for power ) i see same problem two different midi keyboard too
now i use an external ac/dc 9V 300mAmper for my samson graphite 25 and it work maybe hours perfect.
i can tell , when your laptops USB voltage outputs blocked (stopped) or fall down very short time (miliseconds ) your USB device is a mouse or computer keyboard or another device ; they can continue their work from where . We dont feel any problem
but if your midi keyboard is connect your USB port and it dont have another power supply , when voltage fall down or stop very short time (ms) all midi protocol will lost so your all connection is lost and you need restart your DAW and midi keyboard again.
finally if your midi keyboard support external DC power supply i think you need,you must use this
if your midi keyboard only have USB port , you need USB multiplier device WITH external AC/DC power supply
your USB port must to be feed another DC power supply ! You never trust your laptop or PC 's USB power.
I read another topics and another forums, you can do upgrade your BIOS and install your latest USB drivers too