Prophet 600 firmware upgrade revisited

Based on the feedback on beta 2022 (1) there have now been some final additions, changes and fixes, most significantly: Typos and updates of the User Manual Fix for modulation delay glitches on new notes Documented MIDI specification for tool development Various small UI fixes Link to the beta 2022 (2) . If nothing unexpected happens, this will be the release in early July.  But there is one more thing.  Proof reading challenge : if you feel you have the time to read the beta 2022 (2) manuals with scrutiny I vow to donate 50 cents to medecins sans frontieres for every misspelling, typo or grammar mistake that is sent to me. This is not because I feel infallible, but rather that I'd like to see those typos gone and do something meaningful at the same time. Just drop me a message with list of findings. Thanks to all active contributors and also for the interest  from around the world  in this Prophet 600 blog. 

While the old Z80 based Prophet 600 has a software execution problem, the Teensy++ 2.0 based version has a hardware bottleneck: the multiplexers. Already during the alpha testing phase it was interesting to explore the software performance on different units. When performance tuned too hard you get effects of glitching, e.g. intermittent wrong voltages especially during fast pitch changes. Through structured testing we managed to pin it down to the multiplexers, which incidentally were different in all testing units. Now with the beta, there has been one case in which one voice never properly updated - and interestingly the same unit works fine with the 2015 GliGli version, but not with the (considerably tuned) 2022 beta. As that problem, too, was solved by replacing the multiplexers, I thought it is time to post something about the importance of the multiplexers in the Prophet 600 so other can benefit from it. In short: if you have CD4051BE multiplexers (from Texas Instruments), which