USB Midi delay

[grillem]

Hi,

I am experiencing an issue related to #46 and #40.
When using the library and sending midi messages through USB, after around 40 seconds the function starts to have a delay of around 250ms. This issue happens whith an arduino Leonardo while the USB is connetced to a Windows machine, otherwise on Mac or with other architectures (SAMD21) it works as expected.

Is there any way to resolve this issue?

Thanks,
Guillem