Computer: MacBook Pro, OSX 10.10 Yosemite
Software: Studio One v3 Professional (latest update)
Hardware: Roland TR8 using both MIDI and Audio interface
I have MIDI output going to the TR8 using its USB MIDI interface. I am triggering notes on the TR8 from Studio One as well as sending MIDI Clock to it. Every so often the velocity of a note drops very low (may actually be the note being dropped entirely, but it's not easy to spot in the MIDI monitor) which means beats are missing.
To rule out the TR8 being the problem I have set up the same thing in Reaper and cannot replicate the problem there so it would appear to be a Studio One issue.
I *think* it may be related to sending MIDI clock, as with it disabled I haven't replicated the behaviour. I need the clock running to access certain facilities on the TR8 itself so turning it off isn't really an option.