On Sun, Sep 2, 2018 at 3:02 AM, Will J Godfrey <WillGodfrey@musically.me.uk> wrote:

As a matter or interest, the only time I've had missing noteoffs with
standard MIDI was when I had only a single MIDI port, and daisy-chained a sound
canvas and two keyboards (both sending active sensing). One for the
keyboards also had a pedal attached. Having said that I always used good quality
short cables.

a couple of days ago, while working on MIDI Clock support in ardour, i was trying to figure out the origin of some missing Clock (0xf8) messages. they would arrive every 830 samples plus or minus about 30 samples,. but every once in a while, the gap would be twice that.

long story cut short: just changing from using my MOTU Ultralite AVB for MIDI I/O to a Midisport 2x2 fixed the problem. No more missing Clock messages.

could be relevant to stories like the one above. there's no good reason for this, but it is how things are.