Intermittently can't cast any skills

Bug Report ID: #3502172613

playing a lightning spear deadeye - I've noticed in some more dense fights, particularly hourglass in sekhamas but also here in Maps that I can't cast any skills for about 10 seconds. I thought it was a mana issue, but that wasn't the case. Just can't use any skills, marks, etc. Can only dodge and run around for a bit.