I have a really old Insteon PLM 2412UH (I'm guessing the "H" is because of the "HouseLink2 enabled" sticker that's on it from when they swapped out everything years ago). It's been working great until the last week or so.
Mac is Sonoma 14.2.1 and Indigo is 2023.2.
What's happening is that the PLM hears and reports on all the Insteon traffic in the Event Log, but no commands from Indigo work (on, off, status). I get failed messages in Indigo with "no acknowledgement".
Is there a way to figure out if something's wrong with Indigo/Mac vs. the PLM needs replacing (without buying a new one to see if it works)?