In my 15 years of doing Crestron I've never seen a bad serial port. But that's just when one would pop up of course. I have plenty to choose from. I'm testing the RTS/CTS now though and I want to see if that works.

Wait.. How can it be a bad serial port when I can see commands going into the 861 with an analyser but I don't see the response?

No wait, can't be a bad port. Issuing commands should produce a response on the 861, I can see the command go in, but nothing comes out. Once it's lost mind; nothing comes out at all to any command while watching the analyser. Of course I have used multiple cables by the way.

Also years ago I saw this same problem on completely different hardware.

How are you guys wired - 2/3/5 or a full cable with RTS/CTS?
On the Crestron side what handshaking do you have: hardware, software or none?

Come to think of it; although handshaking should only matter when sending data. But maybe if handshaking was wacky some command got sent and the command got corrupted and caused something to get weird.

I don�t know; I think this is some sort of weird random bug. I will try hard to reproduce the problem today. Maybe it�s some weird combo like if you�re pressing the volume when it changes bit-streams.

861v8+ID40, HD621, 808.3, MC200, 8000, 7200HC, 4x 5200, analog sub, iPads.
The MC200 feeds a Crestron source.