Midi Moose. Midi Issues Everywhere After finalizing the Acid Moose 303 clone build my midi usage increased significantly. So did my midi problems. Unfortunately I just couldn't get the Acid Moose midi interface working reliably. Sending too many messages made it freeze and the whole device had to be rebooted. I tried changing opto-isolators, crystals, pretty much everything around the pic microcontroller but nothing helped. Anything more than simple note on and note off messages would make it fail. Unfortunately that midi implementation is significant part of the sound because it mimics many 303 peculiarities so changing to another microcontroller implementation wasn't an option either. Needless to say the source code is not available. I finally gave up debugging it and decided to add a midi filter in front of it to throw out everything except the bare minumum of needed midi note messages. Around the same time I also bought an Elektron Digitakt sequencer/sampler.