sustain pedal causing latency

I am using the damper input and I'm using the Roland, single pedal model that came with the keyboard.

My keyboard can work two ways - midi to interface (with the interface using usb to iMac) or just usb from keyboard to iMac. I don't have a power adapter for my keyboard, so I have to use the usb connection from keyboard to iMac to get it to turn on. I did notice that I had my midi cable also connected to my M4 interface, so I undid that and restarted everything. Still have issues.

If I unplug my pedal, I experience no latency even if I play a lot of notes.

With my pedal connected, if I play my keyboard without pressing the pedal, I don't hear any problems. Again I can play lots of notes at the same time and things sound fine.

With my pedal connected, if I start pressing and releasing the pedal, I will hear hiccups in my playing. It seems to be more about the release of the pedal than just pressing the pedal. If I just press the pedal, the notes will sustain and I won't hear problems. But if I release the pedal cause I am changing chords and I want to sustain a new set of notes, I will hear sometimes hear what sounds like latency to me. The notes will sound but there will be a delay before I hear them, like they get saved up and then release and sound. I'm using the pedal like I would always use it and it's never done this before. I don't like playing my keyboard when it does this and I certainly wouldn't bother recording something.

My pedal has a switch that makes its behavior continuous or switch. Continuous is for using it as a sustain pedal. Switch is for making it like an on/off pedal. Of course it is set to Continuous and for good measure I adjusted that switch to make sure it was clearly in position.

Right now, my best guess is it's either a hardware issue (my pedal is broken) or a software issue (since it sounds like latency). I guess I have to go buy a keyboard pedal and see if it goes away.

OK - I just determined that I updated to Big Sur on 11/13/20 and I last successfully recorded midi with pedal on 10/17/20. So even though I have confirmed that I have the right drivers for my A-88 and M4, the main change has been Big Sur. Is the OS now using that much more of my computer's operating power that's it's impacting my midi connection? Seems so unlikely. Could it be the keyboard driver?

It’s still happening, just not as often, say once every 4 or 8 measures as I am using the pedal. So I’m changing arpeggiated chords, releasing and pressing the pedal ahead of the chord change and the new notes don’t immediately sound when I press the keys but instead sound a split second later as if they were held up and then released and it’s trying to catch up. (I feel like I am simply describing latency.) It’s just an occasional chord and it quickly returns to playing fine. Never had this trouble with the pedal before - it’s definitely a change.

Possibly. I tried to use the pedal a lot to get it to hiccup and it didn’t. What does this Bypass command do? I’ll of course test it some more tomorrow.

Interesting. Changing to Switch may have resolved the issue. I thought I heard one blip so I’m still testing it, but that might be the answer. I will work on getting an a/c adapter so I can try using the midi cable instead. The drivers are up to date and correct for my Big Sur iMac.