PaulS:
I don't see that. It looks like an issue with X-CTU, to me.
I was hoping that was the case. But viewing the Serial Monitor with the XBee hooked up (through the BoB + FTDI at 9600Baud) shows the same garbage streaming through. Same result if I hook the XBee up to an Uno on pins 2 and 3 and using Software Serial to echo to the Serial Monitor. AT vs API mode also makes no difference.
When you say you changed the physical environment exactly what did you do? The XBee XSC Pro has a 28 mile line of sight range so you could be picking up anything.
What it means is I took it from home and brought it to work ~5-6 miles away. I'm only using the wire antenna models atm, and it's a dense urban environment, plus the building at work is death on wireless signals (steel roof, I only get 2 bars on cell phone inside by a window, 5 outside the same window, though I guess 900MHz will penetrate better).
So just make sure your changes did indeed go through.
Yea, they are saving fine. The settings show back up after un-plugging the XBee and closing X-CTU, and then reopening everything. Also there when I go to another computer and read them. I've only been changing one parameter at a time, and using the write button next to said parameter to write them, so I haven't used the upper button yet that sounds like it might be touchy. Otherwise I like the new X-CTU much better than the old version though.
Changing the Preamble ID (HP) didn't affect anything, but something else on that page you mentioned got me thinking:
When a radio is transmitting, it cannot receive packets. When a radio is not sleeping, it is either receiving or transmitting.
The data is perfectly sequential, and pauses whenever a TX is sent from the XBee, and then resumes where it left off. I wonder if what I am seeing is in fact normal behavior for these 900MHz devices based on the above quote from page 33. I played around with the sleep setting and confirmed that the data stops streaming in whenever the module is in sleep, and then continues where it stopped when it comes out of sleep. Some more research is now in order on my part.
I don't really like this behavior, as like I mentioned it will make parsing data received from the XBee onto the Arduino a pain. It will be possible to see data that matches what I might send without me having actually sent it to the remote device. More thinking on my part if this behavior is in fact as designed.