Defiler Spell Issue: Shroud of Armor VII

When zoning into any Skyshrine zone, Shroud of Armor's ward amount drops from 5900 down to 2100 and remains that way.
Within any other zone outside of SS, the ward amount is normally around the 6k range.
Things I've tried:
- Tested with another Defiler. Same issue.
- Relogging
- Recasting the spell
- Verified within ACT that it isn't a graphical bug.
- Tried numerous setups with groups/Raids which don't seem to affect it either way.
- Tried previous versions of the spell and they too are affected.
Am I missing something here?

What's your crit chance? Is it possible the crit chance debuff for Skyshrine zones is reducing you below 100%?

I have 400 crit chance. I did some more testing today and it seems multiple Defilers are having the issue, from those with raid gear to those with quested/faction gear.

It's been like this for a while, well before Skyshrine. It's possible it started with DoV when they put in crit avoidance, as it's when I first started noticing the differences between instances and overland amounts. For some reason, in most overlands the ward is drastically greater than when you are in any instance. I zone to Freeport and get 3x the amount for the ward than when I zone into a Guild Hall. It seems to be related to most crit bonus not applying correctly in any instance, because the ward amount is abysmally low vs what it should be critting for. Yet the numbers seem about right on overlands.