ErriezDS3231 VS Arduino-AppleMIDI-Library

instead of using a i2c scanner as your code suggest i would start with a proven driver.

I'll post the whole thing in a separate message. I've already modified it a little, because there seems to be a quirk in the rtpMIDI implementation that seems to not send a second MIDI message if two of the same type are sent in sequence in the program. Even a few milliseconds delay between them seems to fix it. Here's the github link to the original.

Changing the order of libraries didn't change anything. BUT with that in mind, I tried disabling one of the libraries I wasn't using at the moment: AppleMIDI. The flashing mostly stopped. It flashed for a few times in the beginning, and then stopped almost completely.

Just a thought, in a future build you could go totally wireless (theoretically) if you use: - an ESP8266 or ESP32 with wireless MIDI and - MIDI mixer on Windows.

Just FYI, network MIDI is a thing and you may want to look into it if you haven't before.

As a bonus, the controller I'm using (ESP-01) also has Wi-Fi, so I added on the AppleMIDI library for receiving wireless MIDI (and sending, too, if I so choose). As a final touch I added VirtuinoCM to switch between 3 modes: - MIDI-response - some generic animations - manual colour control.

This is the sketch that worked for me pretty much out of the box. Mac OS has built-in support for Wi-Fi MIDI, but in Windows you'll need to install rtpMIDI. Once the Arduino sketch is loaded and running, rtpMIDI is installed, and both the computer and ESP32 are connected to the same network, the ESP32 should show up in the rtpMIDI control panel.