I really don't know the answer but I read once that the driver programs are generally where latency problems begin. The drivers are how the devices talk to the pc hardware (is my limited understanding). So if this communication is slowed down at all you'll see latency issues. I know nothing about the 400 either but if you had to load a driver on your PC to work with the 400, your pc may not handle that driver as well as it ought to.

I use a Midiman 2x2 interface that requires no specific driver and from that I run standard Midi cables to my synths.... I've never had any trouble.


If you did not have to load a special driver for the 400, then I would think any midi interface might give you the same problem. because then the trouble might be with your PC talking to its own USB port.

It might be worth a try to get a midi interface. There's a cheap 1x1 out now I believe for like 50 bucks. Do you have a friend that can lend you a midi interface just to test it out?

Best wishes.
Bob
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