sc0rdatura

It’s 60/40 Sn/Pb 5C ersin flux. Don’t have the label on the solder anymore but I know that’s what it is.

I have inspected/reflowed the joints around the MIDI jacks but sadly the problem persists. The flux doesn’t seem to be the issue.

  I have inspected all the joints on the board, reflowed (especially those in green) and removed flux for good measure. Solder blobs have also been removed. The issues...

Have tried both the 1x midi setting and confirmed the resistor values are at 1k by Color code and measurement. Still getting the same result.

Can confirm the couplers are getting the correct voltages.

Sadly I don’t have a spare arduino mega, but is the arduino a possibility even if all of the build firmware tests pass?

Yup that all looks good as well. Just did some testing around the midi jacks/couplers with the multimeter and your schematic and everything seems in order.

I’ve been trying both with USB and DC, to see if it would make any difference, but alas not. I don’t have either to test port 2 sadly. Yes I’ve...