
This board is currently being manufactured by JLCPCB in China, and has an expected completion date for this coming Monday.
When I get at least one board assembled and tested, I'll be sure to post the updated schematics, as well as my observations. So far I can tell you that it incorporates the same SIO interface as its predecessor, using a 74LS07 and a 74HCT4066. This new interface has been working very well, and appears to have solved the audio noise issues.
- Michael