MIDI Mysteriously Delayed (sometimes)

[Arcolot]

Hi!

I'm having a strange intermittent MIDI-related issue that I hope is just a newbie error with a bad setting or something. I've searched the forums and couldn't find a recent post related to this problem, so I'm starting a new thread.

I'm using Reaper v6.12c/64 rev 8af23c (Jun 15 2020). I'm on a late 2014 27-inch iMac running macOS Catalina (10.15.5). I'm still in the evaluation phase with Reaper. My input is a Yamaha CP-33 MIDI keyboard that is communicating with Reaper just fine (when I select it for the track, it shows up by name in the Input:MIDI drop-down - I chose All Channels).

Because I'm collaborating with friends, I start with a project that has some other, audio tracks (that is, not MIDI). The track I'm recording into is the only MIDI track. I'm using the Lounge Lizard virtual instrument (an electric piano synth) from Applied Acoustics, which I've used for years with other programs without any problems. The choice of instrument isn't relevant - the problem occurs with any synth I select.

When I start recording, everything works fine. I play, I hear my notes, and my data goes into the track. Then sometimes - and I cannot predict when, or force it to happen, but it's usually within a few minutes of starting the recording - my audio lags about a second behind my keys. Of course, this makes it impossible to play, and I have to stop.

For example, suppose I'm playing along and I press C3. Essentially immediately I'll hear C3. I press D3. I hear D3. And so on. Then I'll press, say, E3. Nothing. And more nothing. And then, after about a second, I'll hear E3. If I then press F3, again I have to wait about a second, and then I'll hear F3. This is the problem, whether I'm playing notes, chords, etc.

Strangely, the other (pre-existing) tracks continue to play, without dropping a note or a moment. It's only the track I'm recording that suffers this problem.

Here's what I've tried so far, and the results:

1. Just keep going and hope the audio locks in again. It doesn't, and my playing gets quickly awful and I stop. Curiously, though, if I play back the recording, the MIDI data (before I fall apart) is on the beat. This suggests that the MIDI is getting read and recorded properly.

2. Close the track and open a new one. The audio delay is still there, right away.

3. Close Reaper and re-open the same project. Everything seems locked in again, but then sometime (usually 3-8 minutes in) the audio problem suddenly returns.

4. Close Reaper and open a new project. Same result as #3.

5. Reboot and re-open Reaper on an old or new project. Same result as #3.

I have other audio software on the computer, of course - Logic and related programs (too many to list here, but they're not running when Reaper is running) - and I haven't had this problem with them. I downloaded the latest version of Reaper, but the problem persists.

Can anyone please help me resolve this? My friends and I would really like to be able to work together by passing Reaper projects around, but this is making it impossible for me.

Thank you!

[Fex]

Originally Posted by Arcolot

I've searched the forums and couldn't find a recent post related to this problem

Try an old one; this might help:

https://forum.cockos.com/showthread.php?t=175007

(Skip to the end.)

[Arcolot]

Thank you, but I don't see how to use that information. The comment at the end seems to refer to an audio driver called "Dummy Audio," but I don't see that. Is there something inside the Mac version of Reaper that corresponds to this "Dummy Audio" driver? I certainly don't want to mess up my system-wide latency and other settings, since I use other software regularly. I don't see anything like this setting in any of the options under Preferences/Audio (if it's relevant, I have "Disable media buffering for tracks with open MIDI editors (recommended)" checked, as they suggest).