ISP:
Comcast

Type of Internet Connection:
Cable

Internet Connection Speed:
30Mbit/s

Date & Time:
12:30 am 12/20/2013

Frequency:
Sometimes


Character Name:
Dart Erhardt

Race:
Race of your character when the issue occurred.
Hyur Male

World:
Durandal

Class/Level:
Black Mage level 50

Area and Coordinates:
Happens mostly in dungeon/instance areas. Very noticable in Garuda Extreme and Wanderer's Palace

Party or Solo:
Full Party for Garuda Extreme and Light party for Wanderer's Palace.

NPC Name:
None

Monster Name:
Garuda/Any dungeon mob

In-Game Time:
2:30pm

Steps:
Detailed steps on how the issue occurred.
For Garuda Extreme:
1: Have tank take aggro from garuda where she originally stands and have them run her directly opposite from there.
2: While she is running to the other side, stand between the 4 rocks (specifically between the first 2 rocks near where your party spawns) and cast fire 3
3: Note that your spell gets interrupted.

For Wanderer's Palace:
1: Target a mob that and start casting a spell.
2: Have the mob change elevation slightly.
3: Note the spell interrupts.

I've noted this often when going through instance fights and it can get very annoying to have to cast something multiple times, when it should have gone through the first time when there are no obstacles preventing me from getting Line of Sight.