I am writing because I spent several hours today trying to get 5-pin MIDI to work with my Teensy 3.2, I followed the schematic located at the PJRC MIDI Library page precisely and am using the code provided for receiving MIDI messages on the same page and it simply does not work. I have the schematic bread boarded, and I even soldered a version of the same schematic (in case my breadboard is getting old), I've tried swapping out the Teensy 3.2 with a brand new one I had in stock, I've switched up the photocouplers with other models and have tried tweaking details on the schematic as per suggestions located on other forums. On the software side of things I have all my libraries and my Arduino IDE (1.8.5) and Teesyduino (1.41) up to date (MIDI Library 4.3.1).
In spite of all my efforts I can not get a single MIDI message to register (I've tried changing the MIDI source as well just for info). The code just loops through its inactivity message. I've looked through the documentation for the code provided on the site and there doesn't seem to be a problem there either. I've tested all the lines with my multimeter and everything seems alright although I do not have an oscilloscope to check logic.
Basically I've run out of steam and ideas but would really like to get cracking on a project using 5-pin MIDI input. Can anyone offer me any help? Is there an issue with the newest versions of the Arduino IDE or the MIDI Library? Any thoughts or suggestions would be greatly appreciated as I've basically hit a wall...
Just for reference the code and schematic I am using can be found here https://www.pjrc.com/teensy/td_libs_MIDI.html