I’m hoping for a response from Roon.
In the meantime, I discovered two potentially relevant DIY projects:
- IntoBlue - wi-fi device for cloud controlling McIntosh via a $19 photon board - GitHub - RobKikta/IntoBlue: Cloud connectivity for Mcintosh Labs audio equipment
- Roon extension McIntosh - allows USB to RS232 GitHub - stefan747/roon-extension-mcintosh: Roon extension for source and volume control of McIntosh equipment
Not sure how to set up the Roon extension, but that route seems most promising. It looks like it can run on a Raspberry Pi instead of my Roon server, which is not close enough to run a USB->RS232 connection to my preamp.