Troubleshooting MMclock: Common Issues and Quick Fixes

MMclock: The Ultimate Guide to Installation and SetupMMclock is a lightweight, flexible MIDI clock and synchronisation tool used by electronic musicians, producers, and live performers to keep hardware and software devices running in time. This guide walks through what MMclock does, how to install it on Windows, macOS, and Linux, how to configure it with common DAWs and hardware, advanced settings, troubleshooting, and practical tips for live performance and studio use.

What is MMclock?

MMclock is a utility that generates, forwards, and translates MIDI clock signals. It can:

Act as a master clock to synchronize multiple MIDI devices.
Receive MIDI clock from another device and forward it to selected ports.
Convert between different timing sources (e.g., MIDI clock, MIDI Time Code, internal tempo).
Provide a stable, low-latency timing reference for setups that include vintage drum machines, modular synths, and modern software.

Key features: lightweight footprint, configurable port routing, adjustable tempo and swing, support for MIDI thru and filtering, and compatibility with multiple platforms.

System requirements

Windows 10 or later, macOS 10.13+ (may vary by build), or a modern Linux distribution.
A MIDI interface (hardware) or virtual MIDI ports (software) for routing between applications.
Basic familiarity with MIDI concepts (clock, BPM, start/stop, ports).

Installation

Note: MMclock may be distributed as a standalone binary, a packaged app, or as part of a suite of MIDI utilities. Below are general installation steps; consult the specific release notes or repository for exact commands and filenames.

Windows

Download the latest Windows build (usually a ZIP or installer).
If ZIP: extract to a folder. If installer: run the installer and follow prompts.
Install or enable any MIDI drivers for your hardware (e.g., ASIO4ALL for audio, manufacturer MIDI drivers).
Ensure virtual MIDI ports (loopMIDI, loopMIDI port drivers) are installed if you need intra-PC routing.
Run mmclock.exe (or the provided shortcut).

macOS

Download the macOS build (DMG or ZIP).
Open the DMG and drag the app to Applications, or extract the ZIP.
If necessary, allow the app in Security & Privacy if macOS blocks it.
Use the Audio MIDI Setup app to verify MIDI devices and virtual ports.
Run MMclock from Applications.

Linux

Obtain the build from the project releases, or compile from source if needed. Typical dependencies: ALSA, Jack, or RtMidi.
If compiling: clone the repository, then run the usual build steps (configure/make or cmake/make). Example (adjust per project instructions):
```
git clone https://example.com/mmclock.git cd mmclock mkdir build && cd build cmake .. make sudo make install 
```
Ensure proper permissions for MIDI devices (ALSA) and install virtual MIDI tools (e.g., aconnect, a2jmidid, and JACK if required).
Run the mmclock binary.

Basic setup and configuration

After installation, the first task is to select MIDI input and output ports and choose whether MMclock will act as Master or Slave.

Open MMclock and find the port/IO settings panel.
Select your MIDI input (if receiving clock) and one or more MIDI outputs (to forward clock).
Choose mode:
- Master: MMclock generates clock and start/stop messages. Set BPM and press Start.
- Slave: MMclock listens to an external MIDI clock and follows tempo/start/stop.
Configure MIDI filtering if you want to block certain messages (e.g., SysEx) or limit forwarding.
Optionally enable sync-to-host or internal metronome output for monitoring.

Integrating with DAWs

Most DAWs can send and receive external MIDI clock. Below are common setups.

Ableton Live

Set Preferences → Link/MIDI.
Enable “Sync” for the virtual MIDI port connected to MMclock.
If MMclock is Master, start MMclock then enable External Sync in Live’s transport. If Live is master, enable Sync in Live and set MMclock as slave.

Logic Pro

Logic can send MIDI Clock to a selected MIDI device in the Environment or MIDI Settings.
In Control Surfaces or MIDI sync settings, enable “MIDI Clock” for the port connected to MMclock.

Reaper

Preferences → MIDI Devices. Enable the output device and allow it to send clock. In Project Settings, set MIDI clock sync to send/receive as needed.

Using with hardware synths and drum machines

Connect your MIDI interface outputs to the DIN MIDI inputs of hardware devices.
If using multiple devices, chain MIDI thru where appropriate, or use MMclock to multi-output to each device.
For analog/semi-modular gear without DIN MIDI, use a MIDI-to-CV interface and ensure clock outputs map correctly to clock/trigger inputs.

Practical tips:

Use short, good-quality MIDI cables and avoid daisy-chaining too many devices through a single thru port.
If devices drift, try letting MMclock be the single master and feed all devices from separate outputs.

Advanced settings

Tempo smoothing: reduces abrupt tempo jumps when following a noisy clock source.
Swing/Shuffle: introduce fixed rhythmic bias; useful for groove.
Clock rate division/multiplication: produce 1:2, 2:1, etc., useful when hardware expects different PPQN.
MIDI Time Code (MTC) translation: convert between MTC and MIDI Clock for DAWs that use SMPTE timecode.

Example: set a 2x multiplier to drive a drum machine that expects 48 PPQN when your source is 24 PPQN.