You're right, now i'm TOTALLY confounded.

I tried the full 2015.10 again in another AU 660, nothing shows. I found a NA 680 in my 'to do drawer' which was bricked. I unbricked it and put the SD into it, again nothing. The card works in every other unit I've tried it in from a 260 thru to a 3597, it show in them np.

There's reports on other forums that ppl had 2014.40 working in 6x0's but can't get 2015.10 working. I've now personally tried it in 4 x 3x0 and 3 x 6x0 without success yet 2014.40 works in all of them.

Not stopping to pick magic mushies on those long hauls between MA & FL are you by any chance. I wouldn't let any fairy, binary or otherwise, touch my unit.

So what's special about your 660 i wonder. Both my 6x0 units are on latest V4.90. What fw version is yours running?