Using windows7 64bit sp1, I tried updating from v1.10 > 2.01 and received the midi error. While screen still displaying "Downloading..." I tried to rollback to v1.10 and recieved midi error again.I then exited monkey and restarted my hd300. Luckily it seemed to be fine and back to v1.10.
Here are changes I made to successfully flash v2.01:
1) Disabled real time anti-virus(microsoft security essentials) and set "usb selective suspend" to "disabled" in power settings.
2) Disconnected hd300 usb and installed drivers v4.5.4 over top of original v4.5.7.
3) Reboot pc
4) Reconnected hd300 usb into different port(happened to be a usb3.0 port this time)
5) Right click on monkey and selected "run as administrator"
6) Flashed 1.10 >1.20>1.31>2.01 consecutively from files on computer(no restarts,no factory resets,no closing monkey)
Hardware and software used:
Core i7 2700k
Gigabyte mobo z77MX-D3H
Windows 7 64bit sp1
usb firmware v1.01
note: I did a factory reset before first failed attempt. Did not do any factory resets after that.