Flashing shield?

echokazul

So I've tried googling this, and have yet to find any answers, so I thought I'd ask here. I'm a recently returning player, and my GF, level 60 last month and now level 70, has had this really annoying blue ghostly shield that keeps popping up in front of her with a metallic chunking noise. It's constantly going off every few seconds, though there doesn't seem to be a rhythm to it. What's causing that?

EDIT: Figured it out! It was my Shadowclad enchantment I had attached to my armor. I think I'll try to find something else. That was really annoying.