Check elsewhere in the forum, there are messages about more people who are having problems with the PR4. A friend of mine sent his back to Digitrax but they say that it is working correctly. We tested it quite thoroughly and could not get it to work before we sent it to Digitrax. So it looks as if the PR4 is not compatible with JMRI. Have you tried the Digitrax programming software? I have a PR3 and it worked quite reliably with JMRI. Only suggestion I have for you, try pushing and holding the two buttons for 5-10 seconds. That seems to do some kind of reset, it might help.
Sorry to rain on your parade
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Stefan Bartelski
Home layout: The Blue Ridge Line, an HO representation of the L&N Etowah Old Line from Etowah to Elizabeth, set in 1986 9under construction)
Modular Layout: Shoofly module of the Country RRoads Modular group
