Hi.

I have my i7 Windows 10 PC connected to an USB Roland UM-ONE (i think it is the MK2).

I am using the PC has a MIDI device running various SF2 files with CoolSoftVirtual MIDI Synth and Midi Player.

So the UM-ONE is directly connected to a MIDI OUT port of my EDIROL UM-500 (no chaining), and i have other devices on my MIDI stack on other OUT ports but never more than two on the same chain.

The computer i use to play MIDI files to my stack is an Amiga 4000 and i can play every synth in my stack (except the i7 PC) at once for a nice polyphony.
When i add the i7 PC to the game, this one is late to play compared to the others (i would say half a second or a second from ear) and the result is of course awful.

I guess this comes from the USB interface rather than CoolSoftVirtual MIDISynth.

Is it usual for the UM-ONE or could i do something to fix it?

Thanks for your help.