There's an oldish techie paper on the subject here
Thanks for the link, I'll be reading that tomorrow stuck in my hotel room with nothing else to do!
The other thing to keep an eye on is the temperature which will cause Mach to fluctuate rapidly.
Ah! This didn't occur to me at the time, so I can't confirm what the temp was doing!
Your best option in that sort of case is to transfer it to Airbus who will decode the DFDR/QAR/DAR data.
Might have been binned by now. I'll have a word with the guys at the base and see if it was an anomaly or a trend!
Just a side note: if you see something similar in the SIM think quickly about jammed stabilizer / THS runaway.
Good to know, I'll put that on my "to look up" list for this week.